Plant Problem Solver

Affects Acalypha wilkesiana

Look for: Tiny white flies swarm when disturbed; sticky honeydew on leaves causes sooty mould.

What to do: Use yellow sticky traps and spray with insecticidal soap or biological controls like Encarsia formosa.

Affects Acalypha wilkesiana · Spring

Look for: White, cottony wax-like masses in leaf axils and on stems; leaves may yellow and drop.

What to do: Dab infestations with a cotton bud dipped in methylated spirit or apply systemic insecticide.

Affects Acalypha wilkesiana

Look for: Fine webbing on stems and leaves; foliage becomes speckled, yellowed, and brittle due to dry air.

What to do: Increase humidity by misting and treat with a horticultural oil or predatory mites like Phytoseiulus persimilis.

Affects Acalypha wilkesiana · Spring, Winter

Look for: Leaves turn yellow and drop rapidly; soil remains waterlogged and may smell musty.

What to do: Ensure pots have drainage holes and allow compost to dry slightly between waterings, especially in winter.

Affects Acalypha wilkesiana · Winter

Look for: Small, immobile, shield-like bumps on stems and undersides of leaves; plant looks unhealthy.

What to do: Scrape off small infestations manually or treat with horticultural oil during the dormant period.

Affects Acanthocalycium spiniflorum

Look for: White, cottony wax patches appear in stem crevices and around the base.

What to do: Isolate the plant and dab infested areas with a cotton bud soaked in methylated spirits.

Affects Acanthocalycium spiniflorum · Winter

Look for: The stem becomes soft, shrivelled, and discoloured brown or black at the base.

What to do: Ensure excellent drainage with gritty compost and withhold water during winter dormancy.

Affects Acanthocalycium spiniflorum

Look for: Small, immobile brown or white bumps attached firmly to the stem surface.

What to do: Scrape off visible scales and treat with a horticultural oil spray during warmer months.

Affects Acanthocalycium spiniflorum

Look for: Pale, bleached, or scorched patches on the side of the cactus facing direct light.

What to do: Gradually acclimatise the plant to brighter conditions before moving it into full sun.

Affects Acanthocalycium spiniflorum

Look for: Semi-circular notches on leaf margins (if present) or sudden collapse due to root damage.

What to do: Use nematode treatments in the soil or apply a systemic insecticide as a preventive measure.

Affects Acer davidii · Spring

Look for: Small, greenish-pink blister-like galls form on the undersides of leaves.

What to do: Usually cosmetic; severe infestations can be treated with horticultural oil in spring.

Affects Acer davidii

Look for: Clusters of small soft-bodied insects on new shoots causing sticky honeydew.

What to do: Encourage natural predators like ladybirds or use a strong jet of water to dislodge them.

Affects Acer davidii

Look for: General decline, dieback, and white fungal growth under bark at the base.

What to do: Ensure well-drained soil; remove infected roots and avoid replanting maples nearby.

Affects Acer davidii · Winter

Look for: Small, brown, shield-like insects on stems and leaves leading to sooty mould.

What to do: Scrape off scales manually or apply horticultural oil during the dormant season.

Affects Acer davidii

Look for: Sudden wilting, browning, and dieback of branches or entire sections of the canopy.

What to do: Avoid planting in infected soil; remove and burn affected trees to prevent spread.

Affects African Milk Barrel

Look for: White, cottony wax-like clusters appear in leaf axils and on stems.

What to do: Isolate the plant and treat infested areas with a cotton bud dipped in methylated spirits.

Affects African Milk Barrel · Winter

Look for: Stem becomes soft, mushy and discoloured, often starting at the base.

What to do: Ensure excellent drainage with gritty compost and avoid overwatering, especially in winter.

Affects African Milk Barrel

Look for: Small, immobile, shield-like bumps attached to stems and leaves.

What to do: Scrape off visible scales and apply horticultural oil or insecticidal soap to control populations.

Affects African Milk Barrel

Look for: White or brown bleached patches on the stem surface exposed to intense light.

What to do: Acclimate plants gradually to brighter conditions and avoid sudden exposure to harsh midday sun.

Affects African Milk Barrel

Look for: Semi-circular notches chewed into leaf margins and wilting despite moist soil.

What to do: Use biological nematodes or systemic insecticides in the compost during active growth periods.

Affects Agapanthus africanus

Look for: Flower buds become deformed, discoloured, and fail to open due to larval feeding inside.

What to do: Remove and burn affected flower heads before seeds set to reduce the population.

Affects Agapanthus africanus · Winter

Look for: Leaves turn black, mushy, or translucent after exposure to freezing temperatures.

What to do: Protect tender varieties with mulch or move containers to a frost-free location in winter.

Affects Agapanthus africanus

Look for: Leaves turn yellow and wilt while the soil remains wet, indicating waterlogged roots.

What to do: Ensure well-drained soil and avoid overwatering; repot if growing in containers with poor drainage.

Affects Agapanthus africanus

Look for: Irregular holes chewed in young leaves or damage to emerging shoots, often with slime trails.

What to do: Use physical barriers like copper tape or apply iron phosphate-based slug pellets.

Affects Agapanthus africanus · Autumn

Look for: Notched edges on leaves above ground and wilting plants due to larvae feeding on roots.

What to do: Apply nematodes to the soil in autumn or use systemic insecticides for severe infestations.

Affects Agave parrasana · Winter

Look for: Leaves turn translucent, grey, or black and become soft due to frost exposure.

What to do: Keep the plant above 5°C in winter and ensure it is completely dry before cold weather arrives.

Affects Agave parrasana

Look for: White, cottony wax-like clusters appear in leaf axils and on stems.

What to do: Isolate the plant and treat infested areas with a cotton bud dipped in methylated spirits or insecticidal soap.

Affects Agave parrasana

Look for: Leaves become soft, mushy, and discoloured as the base of the plant collapses.

What to do: Ensure excellent drainage with gritty compost and water only when the soil is completely dry.

Affects Agave parrasana

Look for: Small, immobile brown or grey bumps attach to leaves and stems, often secreting sticky honeydew.

What to do: Scrape off visible scales manually and apply a systemic insecticide if the infestation is severe.

Affects Agave parrasana · Summer

Look for: Leaves develop bleached, white, or brown necrotic patches on the most exposed surfaces.

What to do: Acclimatise the plant gradually to brighter light and provide shade during intense midday summer sun.

Affects Alder Buckthorn

Look for: Clusters of small soft-bodied insects on new growth, causing sticky honeydew residue.

What to do: Encourage natural predators like ladybirds or spray with a strong jet of water.

Affects Alder Buckthorn

Look for: Small, dark or brown spots appearing on foliage, sometimes leading to premature leaf drop.

What to do: Remove affected leaves and avoid overhead watering to keep foliage dry.

Affects Alder Buckthorn

Look for: White, dusty fungal growth on leaves and stems, potentially causing distortion.

What to do: Improve air circulation and water at the base; apply a sulphur-based fungicide if severe.

Affects Alder Buckthorn

Look for: Wilting and yellowing leaves despite moist soil, indicating poor drainage issues.

What to do: Ensure well-drained soil conditions and avoid overwatering during wet periods.

Affects Alder Buckthorn

Look for: Irregular holes chewed in young leaves and seedlings, often accompanied by slimy trails.

What to do: Use physical barriers like copper tape or crushed eggshells, and hand-pick at night.

Affects Allium

Look for: Leaves develop white, winding trails or brown patches that cause them to wither and die prematurely.

What to do: Remove affected foliage immediately after flowering and burn it to break the pest's life cycle.

Affects Allium · Spring, Autumn

Look for: White lines of dots on foliage followed by wilting, distortion, and eventual rotting of stems and bulbs.

What to do: Cover plants with fine insect-proof mesh during peak fly activity in spring and autumn.

Affects Allium · Winter

Look for: Bulbs become soft, mushy, and discoloured due to waterlogging in heavy or poorly drained soil.

What to do: Plant in well-drained soil or containers and avoid sites that remain wet during winter.

Affects Allium

Look for: Yellowing leaves with a greyish-purple fuzzy mould appearing on the surface.

What to do: Improve air circulation, avoid overhead watering, and remove severely affected foliage.

Affects Allium

Look for: Foliage shows pale green to yellow streaks covered in a greyish-purple fuzzy mould.

What to do: Improve air circulation, avoid overhead watering, and remove severely infected leaves promptly.

Affects Allium · Spring, Autumn

Look for: Young shoots turn yellow, wilt, and collapse while larvae feed on the bulb base underground.

What to do: Plant in autumn or early spring outside peak flight times and use insect-proof netting as a barrier.

Affects Allium · Spring, Autumn

Look for: Leaves turn yellow and wilt as larvae tunnel into the bulb causing rot.

What to do: Use insect-proof netting to exclude adult flies during their active periods in spring and autumn.

Affects Allium

Look for: Bulbs become soft and rotten with distinctive white, cottony fungal growth on the base.

What to do: Avoid planting alliums in infected soil for at least 10 years and ensure excellent drainage.

Affects Allium

Look for: Plants turn yellow and wilt while the bulb base develops a white, fluffy fungal growth.

What to do: Avoid planting alliums in soil previously affected by the disease and ensure good drainage.

Affects Allium

Look for: Irregular holes chewed into young leaves and emerging shoots, often accompanied by slime trails.

What to do: Use physical barriers like copper tape or apply slug pellets around the base of plants.

Affects Allium moly · Spring, Autumn

Look for: White maggots tunnel through leaves and stems, causing distortion and eventual rotting of the bulb.

What to do: Cover plants with fine insect-proof mesh during peak fly activity in spring and autumn.

Affects Allium moly · Spring, Winter

Look for: Bulbs become soft, mushy, and may emit a foul odour due to waterlogging.

What to do: Ensure planting in well-drained soil or containers to prevent saturation during winter.

Affects Allium moly

Look for: Yellowish patches appear on leaves which later develop a grey-purple fuzzy mould.

What to do: Improve air circulation, avoid overhead watering, and remove severely affected foliage.

Affects Allium moly

Look for: Bulbs develop a fluffy white fungal growth and roots turn brown and decay, leading to plant collapse.

What to do: Remove infected plants immediately and avoid replanting alliums in that soil for at least 10 years.

Affects Allium moly

Look for: Irregular holes are eaten into young shoots and leaves, often accompanied by slimy trails.

What to do: Use physical barriers like copper tape or apply iron phosphate-based pellets around the base.

Affects Allium paradoxum

Look for: White, dusty fungal growth appears on leaves and stems, potentially stunting growth.

What to do: Improve air circulation, avoid overhead watering, and apply a fungicide if severe.

Affects Allium paradoxum

Look for: Leaves turn yellow and wilt despite adequate moisture, often due to waterlogged soil.

What to do: Ensure well-draining soil and avoid overwatering; remove affected plants to prevent spread.

Affects Allium paradoxum

Look for: Irregular holes chewed in leaves and flower stems, often with slime trails.

What to do: Use slug pellets, beer traps, or copper tape barriers around the planting area.

Affects Allium paradoxum · Autumn

Look for: Notches on leaf margins during the day and root damage causing wilting at night.

What to do: Apply nematodes to the soil in autumn or use systemic insecticides as a preventive measure.

Affects Alma-Ata Iris

Look for: Rhizomes become soft, mushy, and emit a foul smell, causing the plant to collapse.

What to do: Ensure excellent drainage and air circulation; cut away affected tissue with disinfected tools or discard severely infected plants.

Affects Alma-Ata Iris · Summer

Look for: Base of the plant becomes soft and discolored, often due to waterlogged soil conditions.

What to do: Plant in gritty, free-draining compost and keep dry during summer dormancy; discard any bulbs showing decay before planting.

Affects Alma-Ata Iris · Winter

Look for: Small brown spots with yellow halos appear on leaves, potentially coalescing into larger lesions.

What to do: Remove and dispose of infected foliage at the end of the season to reduce overwintering spores.

Affects Alma-Ata Iris

Look for: Orange or brown pustules form on leaves, leading to yellowing and premature leaf death.

What to do: Improve air circulation around plants and remove heavily infected leaves to slow spread.

Affects Alma-Ata Iris

Look for: Irregular holes chewed in leaves and flowers, often accompanied by silky trails.

What to do: Use physical barriers like copper tape or hand-pick at night; avoid chemical slug pellets where possible.

Affects Aloe · Winter

Look for: Leaves turn grey, shrivel, or become waterlogged and translucent after exposure to freezing temperatures.

What to do: Keep aloes above 10°C in winter and ensure they are not exposed to frost or cold drafts.

Affects Aloe

Look for: White, cottony wax-like clusters appear in leaf axils and on stems, potentially causing yellowing.

What to do: Isolate the plant and treat infestations with a systemic insecticide or dab spots with alcohol-soaked cotton.

Affects Aloe

Look for: Leaves become soft, mushy, and translucent, often starting from the base of the plant.

What to do: Ensure excellent drainage with gritty compost and water sparingly only when the soil is completely dry.

Affects Aloe

Look for: Small, immobile, brown or white bumps attach to leaves and stems, often exuding sticky honeydew.

What to do: Scrape off visible scales manually and apply a horticultural oil spray if infestation is heavy.

Affects Aloe

Look for: Leaves develop bleached, white, or brown patches where they have been exposed to sudden intense light.

What to do: Acclimate plants gradually to brighter conditions and avoid placing them in direct midday sun initially.

Affects Alpine Primrose

Look for: Dark, water-soaked spots develop on foliage, potentially causing leaves to yellow and decay.

What to do: Improve air circulation and avoid wetting foliage when watering to reduce humidity around the plant.

Affects Alpine Primrose

Look for: Clusters of tiny, cup-like spore-producing structures appear on the underside of leaves.

What to do: Remove and destroy infected leaves immediately; avoid fungicides to protect biodiversity.

Affects Alpine Primrose · Winter

Look for: Leaves turn yellow, wilt, and the plant collapses due to waterlogged, poorly drained soil.

What to do: Ensure planting in well-drained soil and avoid overwatering, especially during winter months.

Affects Alpine Primrose

Look for: Irregular holes chewed in leaves and silvery slime trails visible on soil or foliage.

What to do: Use physical barriers like copper tape or hand-pick pests at night; avoid chemical slug pellets where possible.

Affects Altai Tulip · Winter

Look for: Bulbs decay and collapse due to waterlogged soil or poor drainage conditions.

What to do: Plant bulbs in well-drained soil and ensure they do not sit in standing water during winter.

Affects Altai Tulip

Look for: Irregular holes are eaten into emerging shoots, leaves and flower petals.

What to do: Use slug pellets, beer traps or copper tape barriers to protect young growth.

Affects Altai Tulip

Look for: Brown spots appear on leaves which become twisted, withered and distorted.

What to do: Remove infected material immediately and avoid replanting in the same spot for at least three years.

Affects Altai Tulip

Look for: Flowers show irregular colour breaks or streaks and plant vigour declines over time.

What to do: Destroy infected bulbs promptly and control aphid vectors to prevent spread.

Affects Altai Tulip · Spring, Autumn

Look for: Notched edges on leaves above ground and root damage causing wilting below.

What to do: Apply nematode-based biological controls to the soil in autumn and spring.

Affects American Century Plant

Look for: White, cottony fluff accumulates in leaf axils and on stems.

What to do: Isolate the plant and treat with a suitable horticultural oil or insecticide.

Affects American Century Plant · Winter

Look for: Leaves become soft, mushy, and discoloured due to waterlogged soil.

What to do: Ensure sharp drainage with gritty compost and avoid watering during winter dormancy.

Affects American Century Plant

Look for: Small, immobile, waxy bumps appear on stems and leaves.

What to do: Rub off with a cotton bud dipped in methylated spirit or use an insecticidal soap.

Affects American Century Plant · Autumn

Look for: Semi-circular notches on leaf margins and wilting caused by root damage.

What to do: Apply nematodes to the soil in autumn or use a systemic insecticide drench.

Affects American Century Plant · Winter

Look for: Leaves turn translucent, grey, or black and collapse from cold moisture.

What to do: Protect outdoor plants with a cloche or clear plastic sheeting in winter.

Affects Angular Jasmine

Look for: Clusters of small green or black insects on new growth causing distorted leaves and sticky honeydew.

What to do: Squash by hand or spray with a strong jet of water; use insecticidal soap if infestation is severe.

Affects Angular Jasmine

Look for: White, powdery fungal growth on leaves and stems, often leading to leaf distortion and drop.

What to do: Improve air circulation and avoid wetting foliage; treat with a sulphur-based fungicide if necessary.

Affects Angular Jasmine

Look for: Fine webbing on leaves and stems with stippled, yellowing foliage, especially in dry indoor conditions.

What to do: Increase humidity around the plant and spray with water or horticultural oil to dislodge mites.

Affects Angular Jasmine

Look for: Yellowing, wilting leaves despite moist soil, indicating waterlogged roots and potential fungal infection.

What to do: Ensure pots have drainage holes and allow the compost to dry slightly between waterings.

Affects Angular Jasmine

Look for: Small, immobile, bump-like pests attached to stems and leaves, often accompanied by sooty mould.

What to do: Scrape off visible scales with a soft brush or cotton bud dipped in methylated spirit.

Affects Anise-Scented Sage

Look for: Clusters of small green or black insects on new growth, often accompanied by sticky honeydew.

What to do: Squash by hand or spray off with a strong jet of water; use insecticidal soap if infestation persists.

Affects Anise-Scented Sage · Spring

Look for: Leaves develop small, pale spots and may curl or distort as the insects suck sap.

What to do: Encourage natural predators like ladybirds or apply a horticultural oil spray during peak activity.

Affects Anise-Scented Sage

Look for: White, dusty fungal growth appears on leaves and stems, potentially causing distortion.

What to do: Ensure good air circulation and water at the base; treat with a sulphur-based fungicide if severe.

Affects Anise-Scented Sage · Winter

Look for: Stems become soft and mushy at the base while foliage wilts despite moist soil.

What to do: Plant in well-drained soil and avoid overwatering, especially during winter dormancy.

Affects Anise-Scented Sage

Look for: Irregular holes in young leaves and stems, often with silky trails visible on foliage.

What to do: Use physical barriers like copper tape or apply iron phosphate pellets around the base of plants.

Affects Apothecary's Rose

Look for: Clusters of small green or black insects cluster on new shoots and buds, causing stunted growth.

What to do: Squash by hand, blast with water, or use insecticidal soap for heavy infestations.

Affects Apothecary's Rose · Spring, Autumn

Look for: Circular black spots with fringed edges appear on leaves, causing them to yellow and drop prematurely.

What to do: Remove fallen leaves in autumn and apply a fungicide or lime sulphur spray in early spring.

Affects Apothecary's Rose

Look for: Large, rough, tumour-like swellings develop on the stem base or roots, weakening the plant.

What to do: Cut out galls with sterile tools and destroy infected material; avoid replanting roses in affected soil.

Affects Apothecary's Rose

Look for: A white, dusty fungal growth covers new shoots, buds, and the upper surfaces of leaves.

What to do: Improve air circulation by pruning and treat with a sulphur-based fungicide or milk spray.

Affects Apothecary's Rose

Look for: Orange-yellow pustules form on the undersides of leaves, causing them to curl and turn brown.

What to do: Prune out affected growth and apply a systemic fungicide at the first sign of infection.

Affects Apothecary's Rose · Winter

Look for: Small, immobile, brown or white bumps encrust stems and leaves, often accompanied by sticky honeydew.

What to do: Scrape off small infestations manually or apply horticultural oil during the dormant season.

Affects Apple · Spring

Look for: Sunken, discoloured lesions on branches or trunk that may ooze sap and cause dieback of shoots.

What to do: Prune out infected wood well below the lesion during dry weather and disinfect tools between cuts.

Affects Apple · Spring, Autumn, Winter

Look for: Leaves develop greenish-black spots and blotches, often falling early, while fruit may also show dark lesions.

What to do: Collect fallen leaves in autumn to reduce overwintering spores and apply approved fungicides during wet springs.

Affects Apple

Look for: Caterpillars bore into developing fruit, causing premature drop and leaving frass around the entry hole.

What to do: Use pheromone traps to monitor adults and apply targeted sprays or use trunk bands to catch crawling larvae.

Affects Apple

Look for: Shoots and blossoms wilt suddenly, turning black and curling into a characteristic 'shepherd's crook' shape.

What to do: Prune out infected branches well below symptoms during dry weather and avoid excessive nitrogen fertiliser.

Affects Apple

Look for: A white powdery growth appears on young leaves, shoots, and sometimes fruit, potentially reducing tree vigour.

What to do: Prune to improve air circulation and apply sulphur-based treatments or resistant cultivars where possible.

Affects Apple · Winter

Look for: Lumpy outgrowths on bark covered with a white, fluffy waxy substance secreted by the insects.

What to do: Scrape off infested areas in winter or use systemic insecticides; encourage natural predators like ladybirds.

Affects Arctium minus

Look for: Clusters of small soft-bodied insects on new growth, often leaving sticky honeydew.

What to do: Encourage natural predators like ladybirds or blast off with a strong jet of water.

Affects Arctium minus

Look for: White, dusty fungal growth on leaves and stems, potentially causing distortion.

What to do: Improve air circulation and spray with a potassium bicarbonate solution if severe.

Affects Arctium minus

Look for: Irregular holes chewed into young leaves and seedlings, often accompanied by silky trails.

What to do: Use beer traps, copper tape barriers, or iron phosphate-based pellets to control populations.

Affects Arctium minus · Summer, Autumn

Look for: Notched edges on leaves of young plants and root damage causing wilting in seedlings.

What to do: Apply nematodes (Steinernema carpocapsae) to the soil in late summer or autumn.

Affects Ash-Coloured Speedwell

Look for: Clusters of small soft-bodied insects on new growth, accompanied by sticky honeydew.

What to do: Spray off with water or apply insecticidal soap; encourage natural predators like ladybirds.

Affects Ash-Coloured Speedwell

Look for: White, dusty fungal growth appears on leaves and stems, potentially causing distortion.

What to do: Improve air circulation and apply a suitable fungicide if infection is severe.

Affects Ash-Coloured Speedwell

Look for: Plant wilts and collapses despite moist soil, often with blackened, mushy roots.

What to do: Ensure well-draining soil and avoid overwatering; remove severely affected plants.

Affects Ash-Coloured Speedwell

Look for: Irregular holes in foliage and silvery slime trails on leaves and soil surface.

What to do: Use physical barriers, iron phosphate baits, or hand-pick at night to control populations.

Affects Ash-Coloured Speedwell · Autumn

Look for: Notched leaf margins and wilting due to larvae feeding on roots in the pot.

What to do: Apply systemic insecticide drenches or use nematode treatments in early autumn.

Affects Ashy Crane's-Bill

Look for: Small, distorted new growth and silvered or spotted leaves from sap feeding.

What to do: Use insecticidal soap or horticultural oil during the growing season.

Affects Ashy Crane's-Bill

Look for: Yellowing leaves with fuzzy grey-purple growth underneath during wet weather.

What to do: Remove affected foliage and avoid overhead watering to reduce humidity.

Affects Ashy Crane's-Bill

Look for: Skeletalised leaves with large holes chewed by green, slug-like larvae.

What to do: Hand-pick larvae or apply a biological control like nematodes.

Affects Ashy Crane's-Bill

Look for: White, dusty fungal growth on leaves and stems, often in humid conditions.

What to do: Improve air circulation and spray with a fungicide if infection is severe.

Affects Ashy Crane's-Bill · Autumn

Look for: Notches on leaf margins and root damage causing wilting or collapse.

What to do: Apply a systemic insecticide drench in autumn to control larvae in the soil.

Affects Aspen · Spring

Look for: General decline, wilting foliage, and white fungal growth under the bark at the base of the tree.

What to do: Improve drainage and avoid planting in infected soil; severe cases may require removal of the tree.

Affects Aspen

Look for: Skeletonised or chewed leaves with visible larvae or adult insects on foliage.

What to do: Encourage natural predators like birds and wasps; hand-pick severe infestations if necessary.

Affects Aspen

Look for: Sunken, discoloured lesions on branches and trunk with oozing gum or dieback of twigs.

What to do: Prune out infected wood in dry weather and disinfect tools between cuts to prevent spread.

Affects Aspen · Autumn

Look for: Orange or yellow pustules on leaves causing premature yellowing and defoliation.

What to do: Remove fallen leaves to reduce inoculum and ensure good air circulation around the canopy.

Affects Aspen · Autumn, Winter

Look for: Numerous shoots emerging from the base of the tree or roots, creating a dense thicket.

What to do: Cut back suckers at ground level in autumn or winter to maintain tree shape and control spread.

Affects Austrian Pine

Look for: Clusters of small insects on new growth with sticky honeydew residue on needles.

What to do: Wash off infestations with a strong jet of water or apply horticultural oil.

Affects Austrian Pine · Autumn

Look for: General decline, yellowing needles, and white fungal growth at the base in autumn.

What to do: Ensure well-drained soil conditions and remove infected root systems if detected.

Affects Austrian Pine

Look for: Older needles turn brown or grey and drop prematurely, thinning the foliage.

What to do: Improve air circulation around the tree and avoid overhead watering to reduce humidity.

Affects Austrian Pine · Summer

Look for: Caterpillar-like larvae skeletonize and defoliate the needles in summer.

What to do: Hand-pick larvae from small trees or use appropriate biological controls.

Affects Austrian Pine · Spring, Summer

Look for: New shoots wilt, turn brown, and die back in late spring or early summer.

What to do: Apply recommended insecticide sprays to young trees during the flight period of the moths.

Affects Autumn Crocus

Look for: lethal to felines

Affects Autumn Sage

Look for: Tiny jumping insects causing stippled or yellowed leaves and sticky honeydew.

What to do: Spray with a strong jet of water or apply insecticidal soap if infestations are heavy.

Affects Autumn Sage

Look for: White, dusty fungal growth on leaves and stems, potentially causing distortion.

What to do: Ensure good air circulation and water at the base to keep foliage dry.

Affects Autumn Sage · Winter

Look for: Wilting, yellowing leaves, and stunted growth despite adequate moisture.

What to do: Plant in well-drained soil and avoid overwatering, especially in winter.

Affects Autumn Sage

Look for: Small black beetles with orange markings feeding on foliage, causing notching.

What to do: Hand-pick adults and larvae or use biological controls like nematodes.

Affects Autumn Sage

Look for: Irregular holes in leaves and stems, often accompanied by silky slime trails.

What to do: Use physical barriers like copper tape or organic pellets containing iron phosphate.

Affects Avens · Spring

Look for: Larvae shred foliage, causing extensive damage that can be hard for the plant to recover from.

What to do: Monitor from spring onwards and remove any larvae by hand, then destroy them.

Affects Avens · Summer

Look for: Leaves develop brown, crispy edges due to exposure to intense direct sunlight.

What to do: Plant in partial shade or position behind other low-growing plants to soften summer sun.

Affects Avens

Look for: A white, dusty fungal coating appears on leaves and stems, particularly in humid conditions.

What to do: Improve air circulation by thinning crowded plants and water at the base to keep foliage dry.

Affects Avens

Look for: Foliage turns yellow and wilts despite moist soil, indicating poor drainage or waterlogging.

What to do: Ensure soil is well-drained and avoid overwatering, especially for alpine species like G. montanum.

Affects Avens

Look for: Irregular holes in leaves and flower buds, often accompanied by silvery slime trails.

What to do: Use physical barriers like copper tape or organic slug pellets to protect young growth.

Affects Azalea

Look for: Developing flower buds turn brown and die before opening, often linked to leafhopper egg-laying wounds.

What to do: Remove and destroy infected buds promptly if practical; encourage natural enemies of the rhododendron leafhopper.

Affects Azalea

Look for: Foliage turns brown and dies back, with lesions forming under the bark causing dark discolouration.

What to do: Ensure excellent drainage in acidic soil and avoid waterlogging to prevent infection by waterborne spores.

Affects Azalea

Look for: White powdery fungal growth appears on leaves, buds, petals, and shoots, potentially causing distortion.

What to do: Improve air circulation and avoid overhead watering; tolerate mild infections as removal causes severe defoliation.

Affects Azalea

Look for: Creamy white nymphs or bluish-green adults are seen on leaves, leaving cast skins on the undersides.

What to do: Tolerate presence as feeding causes little damage; control is rarely needed unless bud blast is severe.

Affects Azalea

Look for: Leaves develop a silvery sheen on the underside, often with fungal fruiting bodies at the base of stems.

What to do: Prune out and burn affected branches well below the visible symptoms to prevent spread.

Affects Bamboo Iris

Look for: Mottled, distorted, or stunted new growth on young leaves.

What to do: Control aphids early and remove severely infected plants to prevent spread.

Affects Bamboo Iris

Look for: Rhizomes become mushy, blackened, and emit a foul odor.

What to do: Ensure well-drained soil and dispose of infected plants immediately.

Affects Bamboo Iris

Look for: Fuzzy grey fungal growth on dying flower heads or wet foliage.

What to do: Improve air circulation and remove dead flowers promptly to prevent spread.

Affects Bamboo Iris

Look for: Irregular holes chewed in leaves or young shoots damaged.

What to do: Use physical barriers, hand-pick at night, or apply iron phosphate pellets.

Affects Bamboo Iris

Look for: Silvering or bronzing of leaves with small black specks of frass.

What to do: Monitor with blue sticky traps and remove heavily infested foliage.

Affects Banksia Rose

Look for: Clusters of small green or black insects on new shoots causing leaf curling and sticky honeydew.

What to do: Squash by hand, spray with a strong jet of water, or apply insecticidal soap if infestations are severe.

Affects Banksia Rose

Look for: A white, dusty fungal growth covering young leaves, shoots, and flower buds.

What to do: Ensure good air circulation and treat with a sulphur-based or systemic fungicide at first sign.

Affects Banksia Rose

Look for: Fine webbing on stems and stippled, yellowing leaves during hot, dry weather.

What to do: Water the plant thoroughly and spray with horticultural oil or a miticide if damage is extensive.

Affects Banksia Rose · Summer, Autumn

Look for: Distinctive black spots with fringed edges on leaves leading to yellowing and premature leaf drop.

What to do: Remove fallen leaves in autumn and apply a fungicide spray during wet summers to prevent spread.

Affects Banksia Rose

Look for: Dark brown lesions on stems causing canes to shrivel and die back from the tips.

What to do: Cut out affected wood well below the lesion into healthy tissue and disinfect tools between cuts.

Affects Banksia Rose

Look for: Orange or yellow pustules on the undersides of leaves with corresponding brown spots on top.

What to do: Prune out affected growth and apply a recommended fungicide to control severe outbreaks.

Affects Barberry

Look for: Small soft-bodied insects cluster on new growth, causing leaf curling and sticky honeydew.

What to do: Spray off with water, encourage natural predators like ladybirds, or use insecticidal soap.

Affects Barberry

Look for: Caterpillar-like larvae feed on leaves, potentially causing complete defoliation.

What to do: Hand-pick larvae or apply biological controls like nematodes; prune affected shoots if severe.

Affects Barberry

Look for: White, dusty fungal growth appears on leaves and stems, often in humid conditions.

What to do: Improve air circulation, avoid overhead watering, and treat with a fungicide if necessary.

Affects Barberry

Look for: Irregular holes in leaves and silvery slime trails, particularly on young shoots.

What to do: Use physical barriers like copper tape, beer traps, or iron phosphate pellets.

Affects Barberry · Autumn, Winter

Look for: Notched leaf margins above ground and root damage below, leading to wilting plants.

What to do: Apply nematodes to the soil in autumn and winter to control larvae.

Affects Basil-Leaved Rockrose

Look for: White, dusty fungal growth appears on leaves and stems in humid conditions.

What to do: Improve air circulation and spray with a sulphur-based fungicide if severe.

Affects Basil-Leaved Rockrose

Look for: Leaves turn yellow and drop, stems become soft and mushy at the base.

What to do: Ensure planting in sharply draining soil and avoid overwatering.

Affects Basil-Leaved Rockrose

Look for: Irregular holes chewed into young leaves and shoots, often with slime trails.

What to do: Use physical barriers like copper tape or apply iron phosphate pellets.

Affects Basil-Leaved Rockrose · Autumn

Look for: Notched edges on leaves above ground and wilting due to root damage below.

What to do: Apply nematodes to the soil in autumn or use biological controls.

Affects Basil-Leaved Rockrose

Look for: Foliage turns brown and crispy after exposure to frost or cold winds.

What to do: Plant in a sheltered, south-facing position away from frost pockets.

Affects batch 1: 10 plants

Look for: Clusters of small soft-bodied insects on new growth causing distorted leaves.

What to do: Squash by hand or spray with a strong jet of water; use insecticidal soap if severe.

Affects batch 1: 10 plants

Look for: White powdery fungal growth on leaf surfaces, often in humid conditions.

What to do: Improve air circulation and avoid overhead watering; treat with a fungicide if necessary.

Affects batch 1: 10 plants

Look for: Yellowing leaves, wilting despite moist soil, and blackened mushy roots.

What to do: Ensure well-draining compost and avoid overwatering; repot if root damage is evident.

Affects batch 1: 10 plants

Look for: Irregular holes in leaves and silvery slime trails on foliage and soil.

What to do: Use physical barriers like copper tape or apply iron phosphate pellets around the base.

Affects Baum's Pincushion Cactus

Look for: White, cottony fluff appears in stem joints and around the base of spines.

What to do: Isolate the plant and treat with a systemic insecticide or wipe off with alcohol-dampened cotton buds.

Affects Baum's Pincushion Cactus

Look for: The plant becomes soft, mushy, and discoloured at the base.

What to do: Ensure well-draining compost and allow the soil to dry out completely between waterings.

Affects Baum's Pincushion Cactus

Look for: Small, immobile, brown or white bumps adhere to the stems.

What to do: Remove manually with a soft brush or apply a suitable horticultural oil spray.

Affects Baum's Pincushion Cactus · Summer

Look for: Patches of bleached, yellow, or brown tissue on the upper surface exposed to light.

What to do: Gradually acclimatise the plant to brighter conditions and avoid direct midday sun in summer.

Affects Baum's Pincushion Cactus

Look for: Notches appear on leaf margins (if present) and roots are chewed, causing wilting.

What to do: Use nematode treatments in the soil during warm months or apply a systemic insecticide.

Affects Bay Tree

Look for: curling and thickening of the edge of the leaves for the development of the insect's nymphs, eventually creating a necrosed gall

Affects Bay Tree

Affects Bear's Breech

Look for: A white, dusty fungal growth appears on the leaves and stems.

What to do: Improve air circulation around plants and apply a suitable fungicide if severe.

Affects Bear's Breech

Look for: The plant wilts and collapses despite moist soil due to waterlogged conditions.

What to do: Ensure the soil is well-drained and avoid planting in heavy, water-retentive clay.

Affects Bear's Breech

Look for: Irregular holes are eaten in the young foliage, often accompanied by slime trails.

What to do: Use physical barriers like copper tape or apply slug pellets around the base of the plant.

Affects Bear's Breech

Look for: Notches appear on leaf margins while larvae damage roots underground.

What to do: Apply a systemic insecticide to the soil or use nematodes to control larvae.

Affects Bear's Ear

Look for: Clusters of small soft-bodied insects on new growth causing distorted leaves and sticky honeydew.

What to do: Squash by hand, blast off with water, or use insecticidal soap; encourage natural predators like ladybirds.

Affects Bear's Ear

Look for: Fuzzy grey fungal growth on leaves and flowers, particularly in poorly ventilated greenhouses.

What to do: Improve air circulation, avoid wetting foliage, and remove affected plant material promptly.

Affects Bear's Ear · Spring

Look for: Yellow or brown spots on leaves that may enlarge and cause tissue to drop out, leaving holes.

What to do: Remove infected leaves immediately and maintain good garden hygiene to prevent spread.

Affects Bear's Ear

Look for: Clusters of tiny cup-like orange or brown spore structures on the undersides of leaves.

What to do: Remove and destroy infected leaves as soon as symptoms are seen to reduce inoculum.

Affects Bear's Ear

Look for: Notched leaf margins on adults and root damage or wilting caused by grubs, especially in containers.

What to do: Repot into fresh compost annually and use biological nematodes or systemic controls if infestation is severe.

Affects Bearberry

Look for: Small, dark or brown spots appear on the evergreen leaves, potentially causing them to yellow or drop.

What to do: Improve air circulation and remove affected foliage; avoid wetting leaves when watering.

Affects Bearberry

Look for: Yellowing of leaf tissue between green veins due to iron deficiency in alkaline soils.

What to do: Plant only in acid to neutral soil and avoid using lime or hard water for irrigation.

Affects Bearberry · Spring

Look for: Plant wilts despite moist soil, leaves turn yellow or brown, and stems may become soft.

What to do: Ensure well-drained, lime-free soil and avoid overwatering to prevent waterlogging.

Affects Bearberry

Look for: Irregular holes chewed in leaves and silvery slime trails on foliage and surrounding soil.

What to do: Use physical barriers like copper tape, hand-pick at night, or apply iron phosphate pellets.

Affects Bearberry

Look for: Notched edges on leaves above ground and root damage below, leading to wilting or plant collapse.

What to do: Check pots for grubs before planting and apply biological nematodes or systemic insecticides if infested.

Affects Bearded Iris

Look for: Small green or black insects cluster on new growth and flower buds, secreting sticky honeydew.

What to do: Encourage natural predators like ladybirds and lacewings, or blast off infestations with a strong jet of water.

Affects Bearded Iris · Spring

Look for: The base of the plant and rhizome become soft, mushy, and may collapse with a foul smell.

What to do: Ensure well-drained soil and partially exposed rhizomes; cut away affected tissue with a disinfected knife and allow to dry before replanting.

Affects Bearded Iris

Look for: Small purple or brown spots appear on the leaves, often causing them to yellow and die back from the tips.

What to do: Remove and dispose of all leaf debris at the end of the year and pick off lightly infected leaves during the season.

Affects Bearded Iris

Look for: Orange or yellow pustules form on the leaves, leading to yellowing and premature leaf death.

What to do: Improve air circulation around plants and remove infected foliage to slow the spread of spores.

Affects Bearded Iris

Look for: Irregular holes are eaten in the leaves and flower buds, often accompanied by slimy trails.

What to do: Use physical barriers like copper tape or eggshells, and hand-pick pests at night; avoid chemical slug pellets where possible.

Affects Beardtongue

Look for: Clusters of small green or black insects on new growth causing distorted leaves.

What to do: Squash by hand, blast off with water, or use insecticidal soap for severe infestations.

Affects Beardtongue

Look for: Fuzzy grey fungal growth on dying flowers, leaves, or stems in damp conditions.

What to do: Remove affected plant parts immediately and ensure good air circulation to reduce humidity.

Affects Beardtongue

Look for: Distorted, stunted growth with swollen or misshapen buds and leaves.

What to do: Dig up and destroy infected plants; avoid replanting penstemons in the same soil.

Affects Beardtongue

Look for: White powdery fungal growth on leaves and stems, potentially causing leaf distortion.

What to do: Improve air circulation and avoid wetting foliage; treat with a sulphur-based fungicide if necessary.

Affects Beardtongue

Look for: Irregular holes chewed in leaves and stems, often accompanied by silky trails.

What to do: Use physical barriers like copper tape or apply iron phosphate pellets around the base.

Affects Bees' Primrose

Look for: Clusters of small soft-bodied insects on new growth causing distorted leaves.

What to do: Squash by hand, blast with water, or apply insecticidal soap if infestations are heavy.

Affects Bees' Primrose

Look for: A white, dusty fungal growth appears on leaves and flower stems.

What to do: Improve air circulation and spray with a fungicide or bicarbonate solution at first sign.

Affects Bees' Primrose · Winter

Look for: Leaves turn yellow and wilt despite moist soil, often with a mushy base.

What to do: Ensure well-draining soil and avoid waterlogging, especially in heavy clay or winter.

Affects Bees' Primrose

Look for: Irregular holes in leaves and silvery slime trails on foliage and soil.

What to do: Use iron phosphate pellets, beer traps, or hand-pick at night to control populations.

Affects Bees' Primrose · Autumn

Look for: Notched leaf margins and wilting plants due to larvae feeding on roots.

What to do: Apply nematodes to the soil in autumn or use insecticidal drenches for potted plants.

Affects Beet

Look for: meristem and the shoot to languish, eventually leading to heart rot

Affects Begonia semperflorens

Look for: Young seedlings collapse at the base and die rapidly in damp conditions.

What to do: Use sterile, peat-free compost and ensure good ventilation for seed trays.

Affects Begonia semperflorens

Look for: A white, dusty fungal growth appears on leaves and stems, often causing distortion.

What to do: Improve air circulation and apply a fungicide if severe; avoid wetting foliage when watering.

Affects Begonia semperflorens

Look for: Plants wilt and collapse despite moist soil, with blackened, mushy roots.

What to do: Ensure well-drained compost and avoid overwatering; remove affected plants immediately.

Affects Begonia semperflorens

Look for: Irregular holes in leaves and silvery slime trails on foliage and soil surface.

What to do: Use slug pellets, beer traps, or copper tape barriers to protect young plants.

Affects Begonia semperflorens · Autumn

Look for: Notched leaf margins during the day and root damage causing wilting at night.

What to do: Apply nematodes to the soil in autumn or use systemic insecticides for potted plants.

Affects Begonias

Look for: Small green or black insects cluster on new growth and leaf undersides, secreting sticky honeydew.

What to do: Squash by hand or spray with a strong jet of water or insecticidal soap.

Affects Begonias

Look for: A white, dusty fungal growth appears on leaves and stems, often causing distortion.

What to do: Improve air circulation and treat with a suitable fungicide or bicarbonate spray.

Affects Begonias

Look for: Leaves turn yellow and wilt despite moist soil, indicating waterlogged roots.

What to do: Ensure pots have drainage holes and allow compost to dry slightly between waterings.

Affects Begonias

Look for: Irregular holes are eaten in leaves and flowers, often accompanied by slimy trails.

What to do: Use physical barriers, copper tape, or approved slug pellets to protect foliage.

Affects Begonias · Summer, Autumn

Look for: Notched edges on leaves and wilting plants caused by larvae feeding on roots.

What to do: Apply biological nematodes to the compost in late summer or autumn.

Affects Bell Heather

Look for: General decline with wilting leaves and white fungal growth under the bark at the base.

What to do: Remove infected plants completely and avoid replanting ericaceous species in that spot for several years.

Affects Bell Heather

Look for: Foliage turns brown and shrivels rapidly, often starting from the base of the plant in wet conditions.

What to do: Ensure excellent drainage by planting on a slope or in gritty, acid soil to prevent waterlogging.

Affects Bell Heather

Look for: Irregular holes chewed into young shoots or flowers, particularly in damp, sheltered conditions.

What to do: Use slug pellets or beer traps during active periods, ensuring products are safe for ericaceous plants.

Affects Bell Heather · Winter

Look for: Plants appear waterlogged, turn brown, and die back during prolonged periods of cold, wet weather.

What to do: Plant in well-drained soil and avoid heavy mulches that retain moisture around the crown in winter.

Affects Bellflowers · Spring, Autumn

Look for: Distinct circular spots on leaves that may turn brown or black and cause tissue death.

What to do: Clear fallen debris to reduce spores and ensure good airflow around plants.

Affects Bellflowers

Look for: White, dusty fungal growth on leaves and stems, potentially causing distortion.

What to do: Improve air circulation and spray with a fungicide or bicarbonate solution at first sign.

Affects Bellflowers · Winter

Look for: Wilting, yellowing foliage despite moist soil, often due to waterlogged conditions in winter.

What to do: Ensure soil is free-draining and avoid planting in areas prone to winter wet.

Affects Bellflowers

Look for: Orange or brown pustules on the undersides of leaves, leading to yellowing and drop.

What to do: Remove affected foliage immediately and avoid wetting leaves when watering.

Affects Bellflowers

Look for: Irregular holes chewed in leaves and flowers, often accompanied by silky trails.

What to do: Use physical barriers like copper tape or apply iron phosphate-based pellets around the base.

Affects Betula pendula

Look for: Clusters of small soft-bodied insects on new growth, causing sticky honeydew and leaf curling.

What to do: Encourage natural predators like ladybirds or use a strong jet of water to dislodge them.

Affects Betula pendula

Look for: Exit holes in the bark and sawdust-like frass, often on stressed or older trees.

What to do: Maintain tree health through proper watering and mulching; no direct treatment for adults.

Affects Betula pendula

Look for: Leaves develop brown blotches or tunnels as larvae feed inside the tissue.

What to do: Usually cosmetic; remove heavily infested leaves if necessary but often best ignored.

Affects Betula pendula

Look for: Dark, fan-shaped brackets appear at the base of the trunk and the tree shows general decline.

What to do: Improve drainage and avoid planting in infected soil; no effective chemical cure exists.

Affects Betula pendula

Look for: Rapid wilting and yellowing of foliage, often following periods of waterlogged soil.

What to do: Plant in well-drained soil and avoid waterlogging; remove infected roots if detected early.

Affects Betula pendula · Winter

Look for: A white, dusty fungal growth covers the leaves, causing them to curl or distort.

What to do: Ensure good air circulation and prune out affected shoots in winter.

Affects Big-Leaf Rhododendron

Look for: Flower buds turn brown, shrivel, and fail to open before flowering.

What to do: Remove and destroy infected buds promptly to reduce fungal spread.

Affects Big-Leaf Rhododendron

Look for: Upper leaf surfaces show silvery or yellowish stippling with black tar-like spots underneath.

What to do: Encourage natural predators like ladybirds or use insecticidal soap for heavy infestations.

Affects Big-Leaf Rhododendron

Look for: White powdery fungal growth on leaves, buds, and shoots causing distortion.

What to do: Improve air circulation and apply a fungicide if infection is severe.

Affects Big-Leaf Rhododendron

Look for: Small bluish-green insects leap from foliage; nymphs are white on leaf undersides.

What to do: Monitor for damage to flower buds; control is rarely needed as feeding impact is low.

Affects Big-Leaf Rhododendron · Spring

Look for: Leaves develop a silvery sheen underneath and shoots may die back.

What to do: Prune out affected branches well below the infection and burn them.

Affects Big-Leaf Rhododendron · Autumn

Look for: Irregular notches on leaf margins and wilting or collapse of plants due to root feeding.

What to do: Apply nematodes in autumn or use biological controls like Steinernema carpocapsae.

Affects Bigleaf Hydrangea

Look for: White oval waxy patches on stems and leaves, leading to yellowing foliage and reduced vigour.

What to do: Prune out heavily infested branches and treat with horticultural oil during the crawler stage.

Affects Bigleaf Hydrangea

Look for: White oval waxy patches on stems and leaves, leading to yellowing foliage and reduced vigour.

What to do: Prune out heavily infested branches and treat with horticultural oil during the crawler stage.

Affects Bigleaf Hydrangea · Spring

Look for: Dark brown or black spots with yellow halos develop on leaves, which may eventually drop.

What to do: Remove affected foliage and avoid wetting leaves when watering to reduce fungal spread.

Affects Bigleaf Hydrangea · Spring

Look for: Dark brown or black spots with yellow halos develop on leaves, which may eventually drop.

What to do: Remove affected foliage and avoid wetting leaves when watering to reduce fungal spread.

Affects Bigleaf Hydrangea

Look for: A white, dusty fungal growth appears on leaves and flower buds, causing distortion.

What to do: Improve air circulation, avoid overhead watering, and apply a sulphur-based fungicide if severe.

Affects Bigleaf Hydrangea

Look for: A white, dusty fungal growth appears on leaves and flower buds, causing distortion.

What to do: Improve air circulation, avoid overhead watering, and apply a sulphur-based fungicide if severe.

Affects Bigleaf Hydrangea

Look for: Irregular holes chewed in leaves and stems, often accompanied by silvery slime trails.

What to do: Use physical barriers like copper tape or crushed eggshells, and apply iron phosphate pellets.

Affects Bigleaf Hydrangea

Look for: Irregular holes chewed in leaves and stems, often accompanied by silvery slime trails.

What to do: Use physical barriers like copper tape or crushed eggshells, and apply iron phosphate pellets.

Affects Bigleaf Hydrangea · Spring, Autumn

Look for: Notched edges on leaves during the day and root damage causing wilting at night.

What to do: Apply systemic insecticide granules to the soil in spring and autumn to control larvae.

Affects Bigleaf Hydrangea · Spring, Autumn

Look for: Notched edges on leaves during the day and root damage causing wilting at night.

What to do: Apply systemic insecticide granules to the soil in spring and autumn to control larvae.

Affects Birch-Leaved Bellflower

Look for: Small, dark or brown spots develop on foliage, sometimes leading to yellowing leaves.

What to do: Remove affected leaves and avoid wetting foliage when watering to reduce humidity.

Affects Birch-Leaved Bellflower

Look for: White, dusty fungal growth appears on leaves and stems, potentially causing distortion.

What to do: Ensure good air circulation and spray with a fungicide if infection is severe.

Affects Birch-Leaved Bellflower · Winter

Look for: Plant wilts and collapses despite moist soil due to waterlogged conditions in winter.

What to do: Plant in gritty, well-drained compost and avoid overwatering during the dormant season.

Affects Birch-Leaved Bellflower

Look for: Irregular holes chewed in leaves and stems, often accompanied by silky slime trails.

What to do: Use physical barriers like copper tape or apply iron phosphate pellets around the base.

Affects Black Iris

Look for: Rhizomes become mushy, blackened and emit a foul odour, causing the plant to collapse.

What to do: Ensure well-drained soil with rhizomes partially exposed; cut away infected tissue and disinfect tools.

Affects Black Iris

Look for: Black, inky patches appear on bulb scales or rhizomes, leading to rot and plant failure.

What to do: Dispose of affected plants immediately and rest the soil from irises for several years.

Affects Black Iris · Winter

Look for: Small purple or brown spots appear on leaves, often merging to cause yellowing and dieback.

What to do: Remove and dispose of all leaf debris at the end of the year to reduce overwintering spores.

Affects Black Iris

Look for: Orange or brown pustules form on leaves, accompanied by yellowing and premature leaf death.

What to do: Pick off lightly infected leaves to slow spread, but avoid removing too much foliage.

Affects Black Iris

Look for: Young leaves show mottling, streaking, or distortion, reducing vigour and flower quality.

What to do: Dispose of severely affected plants to prevent transmission to neighbouring healthy irises.

Affects Blackberry

Look for: Fruits are pecked, damaged, or entirely stripped from the canes during ripening.

What to do: Cover the crop with bird netting or horticultural fleece once fruits begin to colour.

Affects Blackberry

Look for: Fruits and flowers become covered in a fuzzy grey spore mass and rot rapidly.

What to do: Improve air circulation by pruning and ensure good drainage to reduce humidity around the plants.

Affects Blackberry

Look for: A white, dusty fungal growth appears on young leaves, shoots, and developing fruit.

What to do: Prune for open habit and apply a suitable fungicide if infection is severe in hot weather.

Affects Blackberry

Look for: Orange or yellow pustules develop on the undersides of leaves, causing them to yellow and drop.

What to do: Remove and destroy infected leaves to reduce spore spread and improve air circulation.

Affects Blackberry

Look for: Irregular holes are eaten into young leaves and soft, ripening fruit.

What to do: Use physical barriers like copper tape or apply slug pellets around the base of plants.

Affects Blackthorn

Look for: Clusters of small soft-bodied insects on new growth causing leaf curling and sticky honeydew.

What to do: Encourage natural predators like ladybirds or use a strong jet of water to dislodge them.

Affects Blackthorn

Look for: Flowers turn brown and shrivel prematurely without opening fully, often accompanied by blackening of buds.

What to do: Improve air circulation and avoid wetting foliage when watering to reduce fungal pressure.

Affects Blackthorn · Spring

Look for: Flower buds are stripped from branches in early spring, leaving bare stems before flowering.

What to do: Erect netting or bird deterrents around the shrub during the budding stage.

Affects Blackthorn

Look for: Irregular holes chewed into leaves by various moth larvae feeding on foliage.

What to do: Monitor for webbing or frass and remove affected branches if infestation is severe.

Affects Blackthorn · Spring, Summer, Winter

Look for: Leaves develop a silvery sheen and shoots may die back, often following winter pruning wounds.

What to do: Prune only in mid-summer to allow wounds to heal before fungal spores are active.

Affects Blireana Plum

Look for: Clusters of small soft-bodied insects suck sap from new growth causing leaf distortion.

What to do: Encourage natural predators like ladybirds or use a strong jet of water to dislodge them.

Affects Blireana Plum · Summer

Look for: Sunken, discoloured lesions on stems with oozing gum and dieback of branches.

What to do: Prune out affected wood in dry weather during summer to prevent spread.

Affects Blireana Plum

Look for: White powdery fungal growth appears on young leaves, shoots, and flowers.

What to do: Improve air circulation by thinning the canopy and apply a suitable fungicide if severe.

Affects Blireana Plum · Spring

Look for: Leaves develop a silvery sheen and branches may die back due to fungal infection.

What to do: Prune out infected wood well below the visible symptoms and burn it immediately.

Affects Blireana Plum

Look for: Sudden wilting and yellowing of leaves on one side of the plant with no external cause.

What to do: Remove and destroy infected plants and avoid replanting Prunus in that soil for years.

Affects Blood Iris

Look for: The base of the plant and rhizome become soft, mushy, and emit a foul smell.

What to do: Cut away affected tissue with a disinfected knife, let wounds dry, and ensure well-drained soil conditions.

Affects Blood Iris

Look for: Black, inky patches develop on the bulb scales or rhizome, often causing rot.

What to do: Dispose of affected plants immediately and rest the soil from bulbous irises for several years.

Affects Blood Iris

Look for: Small, circular brown or purple spots appear on the leaves, often merging to cause yellowing.

What to do: Remove and dispose of infected foliage at the end of the year and avoid wetting leaves when watering.

Affects Blood Iris · Winter

Look for: Orange or yellow pustules form on the leaves, leading to general yellowing and decline.

What to do: Pick off lightly infected leaves to slow spread and clear all leaf debris annually to reduce overwintering spores.

Affects Blood Iris

Look for: Young leaves show mottling, streaking, or distortion, reducing plant vigour and flower quality.

What to do: Remove and destroy infected plants to prevent spread to neighbouring healthy irises via tools or contact.

Affects Blue Allium · Spring

Look for: Bulbs become soft, mushy, and may emit a foul odor, often leading to plant collapse.

What to do: Plant in well-draining soil and avoid waterlogging to prevent fungal or bacterial decay.

Affects Blue Allium

Look for: White, dusty fungal growth on leaves and stems, potentially causing distortion.

What to do: Ensure good air circulation and apply a sulphur-based fungicide if infection is severe.

Affects Blue Allium

Look for: Irregular holes in leaves and flower heads, often accompanied by slimy trails.

What to do: Use copper tape barriers, beer traps, or iron phosphate-based pellets to control populations.

Affects Blue Allium · Autumn

Look for: Notched edges on leaves above ground and root damage below, causing wilting.

What to do: Apply nematode treatments in autumn or use systemic insecticides to target larvae.

Affects Blue Garlic · Spring, Autumn

Look for: White blotches on leaves followed by wilting, twisting, and rotting of foliage and stems.

What to do: Cover plants with fine insect-proof mesh during peak fly activity in spring and autumn.

Affects Blue Garlic

Look for: Yellowish patches on leaves that develop into a fuzzy grey-green mould in humid conditions.

What to do: Improve air circulation and avoid overhead watering to keep foliage dry.

Affects Blue Garlic · Spring

Look for: Leaves turn yellow and wilt as maggots tunnel into the bulb from the base.

What to do: Use insect-proof netting to exclude adult flies during their spring emergence period.

Affects Blue Garlic

Look for: Yellowing leaves and a white, powdery fungal growth at the base of the bulb.

What to do: Remove affected plants immediately and avoid replanting alliums in that soil for many years.

Affects Blue Garlic

Look for: Irregular holes chewed into young shoots and leaves, often accompanied by slime trails.

What to do: Use physical barriers like copper tape or apply iron phosphate-based pellets around the base.

Affects Bluebell

Look for: Bulbs become soft, mushy, and discoloured, often leading to plant failure or failure to emerge.

What to do: Ensure well-drained soil and avoid waterlogging; remove and discard infected bulbs immediately.

Affects Bluebell · Summer

Look for: Reduced flowering and smaller blooms due to dense competition for nutrients and space.

What to do: Dig up and divide congested clumps in summer after foliage has died down.

Affects Bluebell

Look for: A white, dusty fungal growth appears on leaves and flower stems in humid conditions.

What to do: Improve air circulation around clumps and apply a fungicide if infection is severe.

Affects Bluebell

Look for: Irregular holes chewed in emerging leaves or flowers, often accompanied by silvery slime trails.

What to do: Use beer traps, copper tape barriers, or iron phosphate-based pellets to protect young shoots.

Affects Bluebell · Autumn

Look for: Notched edges on foliage and wilting plants caused by larvae feeding on bulbs underground.

What to do: Apply nematodes (Steinernema carpocapsae) to moist soil in autumn or use systemic insecticides.

Affects Bodnant Viburnum

Look for: Small, dark brown or black spots appear on leaves, sometimes surrounded by yellow halos.

What to do: Remove affected leaves and avoid wetting foliage when watering to reduce humidity.

Affects Bodnant Viburnum

Look for: White, dusty fungal growth appears on leaves and shoots, potentially causing distortion.

What to do: Improve air circulation and apply a systemic fungicide if severe; resistant cultivars are available.

Affects Bodnant Viburnum · Winter

Look for: Small, immobile, bump-like pests cluster on stems and undersides of leaves.

What to do: Scrape off small infestations or apply horticultural oil during the dormant season.

Affects Bodnant Viburnum

Look for: Irregular holes chewed in leaves and silvery slime trails on foliage and stems.

What to do: Use iron phosphate pellets, copper tape barriers, or hand-pick at night.

Affects Bodnant Viburnum · Autumn

Look for: Notched edges on leaves above ground and root damage below, leading to wilting or collapse.

What to do: Apply nematodes (Steinernema kraussei) to soil in autumn or use systemic insecticides.

Affects Borage

Look for: Winding, pale tunnels or blotches visible within the leaf tissue as larvae feed inside.

What to do: Remove and destroy heavily infested leaves; encourage natural predators like parasitic wasps.

Affects Borage

Look for: A white, dusty fungal growth appears on leaves and stems, potentially causing distortion.

What to do: Improve air circulation, avoid overhead watering, and treat with a sulphur-based fungicide if severe.

Affects Borage

Look for: Plants wilt and yellow despite moist soil, with stems becoming soft or mushy at the base.

What to do: Ensure well-drained soil and avoid waterlogging; remove affected plants to prevent spread.

Affects Borage

Look for: Irregular holes chewed in young leaves and stems, often accompanied by slimy trails.

What to do: Use physical barriers like copper tape or crushed eggshells, or apply iron phosphate pellets.

Affects Borage · Spring, Autumn

Look for: Notched edges on leaves during the day, with root damage causing wilting at night.

What to do: Apply nematodes to the soil in autumn and spring to control larvae, or use biological controls.

Affects Bosnian Pine

Look for: Green caterpillar-like larvae feed on new shoots, causing defoliation and stunted growth.

What to do: Hand-pick larvae or apply insecticidal soap; biological controls like parasitic wasps are also effective.

Affects Bosnian Pine

Look for: Foliage turns brown and needles drop prematurely, often accompanied by a general decline in vigor.

What to do: Ensure excellent drainage and avoid overwatering; do not plant in heavy clay or waterlogged soil.

Affects Bosnian Pine

Look for: Branches bend or break under the weight of heavy snow, leading to structural damage.

What to do: Gently brush snow off branches using a broom; avoid shaking trees as this can cause more damage.

Affects Bosnian Pine

Look for: Fine webbing on needles with stippled or yellowing foliage, worsening in hot, dry conditions.

What to do: Spray affected areas with a strong jet of water to dislodge mites and maintain adequate humidity.

Affects Bosnian Pine · Winter

Look for: Needles turn brown or reddish, particularly on the windward side of the tree during dry, windy winters.

What to do: Water deeply before the ground freezes and use windbreaks to protect young trees from drying winds.

Affects Boxwood

Look for: Leaves turn brown or black with white fungal spores, and stems develop dark lesions causing dieback.

What to do: Prune out affected growth in dry weather, improve air circulation, and isolate new plants for four weeks.

Affects Boxwood · Spring

Look for: Thickened, rusty blister-like pustules appear on both sides of the leaves, particularly in spring.

What to do: Clip off affected shoots during dry weather and dispose of them to reduce spore spread.

Affects Boxwood

Look for: Caterpillars skeletonise leaves leaving only veins, often accompanied by visible webbing on the foliage.

What to do: Hand-pick caterpillars or use biological controls like nematodes; prune out heavily infested shoots.

Affects Boxwood

Look for: Plants decline rapidly and fail completely with no obvious above-ground cause, often in waterlogged soil.

What to do: Ensure well-draining soil conditions and avoid overwatering to prevent root suffocation and fungal attack.

Affects Boxwood · Autumn

Look for: Small pink fungal fruiting bodies appear on dead or dying leaves, often following stress or wet clipping.

What to do: Improve cultural conditions by pruning diseased branches in dry weather and removing fallen leaves.

Affects Brilliant Fuchsia

Look for: Clusters of small green or black insects on new growth and flower buds, often leaving sticky honeydew.

What to do: Squash infestations by hand or spray with a strong jet of water; introduce ladybirds for biological control.

Affects Brilliant Fuchsia

Look for: Shoot tips become swollen, distorted, and discoloured with yellowish-green or reddish tissue instead of normal leaves.

What to do: Prune out affected growth immediately and dispose of it in household waste to prevent spread.

Affects Brilliant Fuchsia

Look for: White, powdery fungal growth on leaves and stems, potentially causing leaf distortion and premature drop.

What to do: Ensure good air circulation and avoid wetting foliage when watering; treat with a sulphur-based fungicide if necessary.

Affects Brilliant Fuchsia

Look for: Fine webbing on leaves and stippled, yellowing foliage, particularly in dry, warm greenhouse conditions.

What to do: Increase humidity around plants and treat with a horticultural oil or insecticidal soap if infestation is severe.

Affects Brilliant Fuchsia

Look for: Irregular holes chewed in soft new foliage and stems, often accompanied by silky slime trails.

What to do: Use physical barriers like copper tape or apply iron phosphate-based pellets around the base of plants.

Affects Bristle-Pointed Iris

Look for: Rhizomes become mushy, discoloured, and emit a foul odour.

What to do: Discard infected plants immediately and ensure soil is well-drained to prevent recurrence.

Affects Bristle-Pointed Iris · Autumn, Winter

Look for: Small, circular brown spots with yellow halos appear on the foliage.

What to do: Remove affected leaves and clear all debris in autumn to reduce overwintering spores.

Affects Bristle-Pointed Iris

Look for: Orange or brown powdery pustules develop on the undersides of leaves.

What to do: Pick off lightly infected leaves and improve air circulation around plants.

Affects Bristle-Pointed Iris

Look for: Irregular holes chewed in leaves and flowers, often accompanied by silky trails.

What to do: Use physical barriers like copper tape or crushed eggshells, and hand-pick at night.

Affects Broad Bean

Look for: Clusters of black aphids cluster on shoot tips, causing stunted growth and distorted leaves.

What to do: Pick off the tips of shoots to reduce infestation and improve yield.

Affects Broad Bean

Look for: Small, dusty, dark brown spots surrounded by a pale yellow halo on leaves and stems.

What to do: Maximise air flow with wider spacing and destroy infected material to prevent spread.

Affects Broad Bean

Look for: Circular emergence holes in dry stored seeds with grubs feeding inside the cotyledons.

What to do: Inspect saved seeds for damage; most affected seeds will still germinate successfully.

Affects Broad Bean · Winter

Look for: Dark, chocolate-coloured spots appear on leaves, stems and pods, potentially causing defoliation.

What to do: Remove infected plant debris after harvest to reduce overwintering spores.

Affects Broad Bean

Look for: Small greyish beetles feed on flowers, reducing pod set and potentially transmitting disease.

What to do: Monitor plants during flowering and remove affected flowers if infestation is heavy.

Affects Bromfield's Living Stone

Look for: White, cottony wax-like clusters appear in crevices and on the surface of the leaves.

What to do: Isolate the plant and treat with a systemic insecticide or dab spots with alcohol-soaked cotton.

Affects Bromfield's Living Stone · Winter

Look for: Leaves swell excessively, become translucent, or split prematurely before natural shedding.

What to do: Reduce watering frequency significantly, especially during winter dormancy and cloudy weather.

Affects Bromfield's Living Stone

Look for: The plant becomes soft, mushy, and discoloured, often collapsing at the base.

What to do: Water sparingly, ensure excellent drainage with gritty compost, and allow soil to dry completely between waterings.

Affects Bromfield's Living Stone · Summer

Look for: Leaves develop bleached, white, or brown necrotic patches on exposed surfaces.

What to do: Acclimatise gradually to bright light and avoid placing in direct midday summer sun initially.

Affects Bryonia dioica

Look for: A white, dusty fungal growth appears on leaves and stems, particularly in humid conditions.

What to do: Improve air circulation around the plant and apply a suitable fungicide if infection becomes severe.

Affects Bryonia dioica

Look for: Foliage turns yellow and wilts despite adequate moisture, indicating waterlogged soil conditions.

What to do: Ensure the planting site has well-drained soil to prevent water accumulation around the tuberous roots.

Affects Bryonia dioica

Look for: Irregular holes are eaten into young leaves and shoots, often accompanied by slimy trails.

What to do: Use physical barriers like copper tape or apply organic slug pellets around the base of the plant.

Affects Bryonia dioica

Look for: Ingestion of any part of the plant, particularly the red berries, causes severe gastrointestinal distress.

What to do: Wear protective gloves when handling and ensure children and pets do not consume the berries or foliage.

Affects Bryonia dioica

Look for: The plant climbs rapidly using tendrils, shading out and physically suppressing neighbouring vegetation.

What to do: Control by manually pulling up young shoots or cutting stems to prevent re-establishment from the tuberous root.

Affects Bugle

Look for: Leaf edges turn brown and crispy due to exposure to intense sunlight.

What to do: Plant in partial shade or ensure consistent moisture during hot spells.

Affects Bugle

Look for: A white, dusty fungal growth appears on the leaves and stems.

What to do: Improve air circulation and apply a fungicide if infection is severe.

Affects Bugle · Winter

Look for: Leaves turn yellow and wilt despite moist soil conditions.

What to do: Ensure the soil is well-drained and avoid overwatering, especially in winter.

Affects Bugle

Look for: Irregular holes are eaten in the soft foliage, often accompanied by slime trails.

What to do: Use physical barriers like copper tape or organic slug pellets to protect plants.

Affects Bugle

Look for: Notched edges on leaves and wilting due to root damage in the soil.

What to do: Apply a systemic insecticide drench or use nematodes to control larvae.

Affects Bukhara Iris · Spring

Look for: Bulbs become soft, mushy, and may show white or grey fungal growth.

What to do: Ensure well-drained soil and avoid waterlogging; discard infected bulbs.

Affects Bukhara Iris

Look for: Small, circular brown spots appear on leaves, potentially causing yellowing.

What to do: Remove affected foliage and improve air circulation around plants.

Affects Bukhara Iris

Look for: White, powdery fungal growth on leaves and stems.

What to do: Spray with a fungicide or milk solution; ensure good airflow.

Affects Bukhara Iris

Look for: Irregular holes chewed in leaves and flowers, often with slimy trails.

What to do: Use physical barriers like copper tape or apply iron phosphate pellets.

Affects Bukhara Iris · Spring, Autumn

Look for: Notched leaf margins and damaged roots causing plant wilting.

What to do: Apply systemic insecticide drenches to soil in autumn and spring.

Affects Bulb Onion

Affects Bulb Onion

Affects Bulb Onion

Look for: rotting

Affects Bulb-Bearing Leopard Lily · Spring, Winter

Look for: The bulb becomes soft, mushy, and may emit a foul odour while foliage yellows and collapses.

What to do: Ensure excellent drainage in compost and allow bulbs to dry completely during their dormant period.

Affects Bulb-Bearing Leopard Lily

Look for: Leaves turn yellow and translucent while the bulb softens due to waterlogged soil conditions.

What to do: Water sparingly during dormancy and ensure pots have adequate drainage holes.

Affects Bulb-Bearing Leopard Lily

Look for: A white, dusty fungal growth appears on leaves and flower stems, often in humid conditions.

What to do: Improve air circulation around plants and treat with a suitable fungicide if infection is severe.

Affects Bulb-Bearing Leopard Lily

Look for: Irregular holes are chewed into young leaves and emerging flower spikes, often leaving slime trails.

What to do: Use slug pellets, beer traps, or hand-pick pests at night to protect tender growth.

Affects Bulb-Bearing Leopard Lily · Autumn

Look for: Notched edges on leaves indicate adult feeding, while larvae damage roots causing plant decline.

What to do: Apply nematodes to the soil in autumn or use a systemic insecticide drench for prevention.

Affects Bulley's Primrose

Look for: Clusters of small soft-bodied insects on new growth, stems, or undersides of leaves.

What to do: Squash by hand or blast off with water; encourage natural predators like ladybirds.

Affects Bulley's Primrose

Look for: Fine webbing and stippled yellowing on leaves, particularly in dry, warm conditions.

What to do: Increase humidity around the plant and spray leaves with water to dislodge mites.

Affects Bulley's Primrose

Look for: Clusters of tiny, cup-like orange or brown spore-producing structures on the leaf underside.

What to do: Remove and destroy infected leaves immediately to prevent spread; improve air circulation.

Affects Bulley's Primrose

Look for: Irregular holes chewed in leaves, often with silvery slime trails visible on foliage.

What to do: Use physical barriers like copper tape or hand-pick at night; avoid chemical slug pellets where possible.

Affects Bulley's Primrose · Spring, Autumn

Look for: Notched edges on leaves above ground and root damage causing wilting or collapse below.

What to do: Apply nematodes to the soil in autumn and spring, or use biological controls for larvae.

Affects Butterfly-Bush

Look for: spreads on open land, railway lines, urban areas and in gardens

What to do: deadheading blossoms to prevent seeding

Affects Buttonhead Primrose

Look for: Clusters of small soft-bodied insects on new growth, often accompanied by sticky honeydew.

What to do: Spray off with a strong jet of water or treat with insecticidal soap or natural predators like ladybirds.

Affects Buttonhead Primrose

Look for: Circular brown or black spots develop on foliage, potentially leading to leaf drop.

What to do: Remove infected leaves and avoid wetting foliage when watering to reduce humidity around the plant.

Affects Buttonhead Primrose

Look for: White powdery fungal growth appears on leaves and flower heads, often causing distortion.

What to do: Improve air circulation and apply a fungicide or bicarbonate spray at first sign of infection.

Affects Buttonhead Primrose

Look for: Leaves turn yellow and wilt despite moisture, with a mushy, darkened root system.

What to do: Ensure well-draining soil and avoid overwatering; remove affected plants to prevent spread.

Affects Buttonhead Primrose

Look for: Irregular holes chewed in leaves and flower buds, accompanied by slimy trails.

What to do: Use physical barriers like copper tape or apply iron phosphate-based slug pellets around the base.

Affects Byzantine Crocus · Winter

Look for: Corms become soft, mushy and discoloured, often leading to plant failure or death.

What to do: Ensure well-drained soil and avoid waterlogging, especially during storage or wet winters.

Affects Byzantine Crocus

Look for: A white, powdery fungal growth appears on leaves and stems, potentially stunting growth.

What to do: Improve air circulation and apply a fungicidal spray if infection becomes severe.

Affects Byzantine Crocus

Look for: Corms are dug up and eaten from the soil, leaving empty holes in the planting area.

What to do: Plant corms deep enough or use wire mesh barriers to protect them from digging animals.

Affects Byzantine Crocus

Look for: Irregular holes chewed into leaves and flowers, often accompanied by slime trails.

What to do: Use slug pellets, beer traps, or encourage natural predators like birds and hedgehogs.

Affects Byzantine Crocus · Summer

Look for: Irregular notches on leaf margins from adults; sudden wilting and root loss from larvae.

What to do: Apply biological nematodes to the soil in late summer or use chemical drenches for containers.

Affects Campanula cochlearifolia

Look for: Clusters of small green or black insects on new growth, causing curled leaves and sticky honeydew.

What to do: Spray off with a strong jet of water or apply insecticidal soap; encourage natural predators like ladybirds.

Affects Campanula cochlearifolia

Look for: White, dusty fungal growth appears on leaves and stems, potentially causing distortion.

What to do: Ensure good air circulation and water at the base; treat with a sulphur-based fungicide if severe.

Affects Campanula cochlearifolia

Look for: Leaves turn yellow and wilt despite moist soil, indicating root decay from waterlogging.

What to do: Plant in well-draining soil and avoid overwatering; remove affected plants to prevent spread.

Affects Campanula cochlearifolia

Look for: Irregular holes chewed in leaves and stems, often accompanied by silvery slime trails.

What to do: Use beer traps, copper tape barriers, or iron phosphate-based pellets to control populations.

Affects Campanula cochlearifolia · Autumn

Look for: Notched edges on leaves above ground and wilting plants due to larvae feeding on roots.

What to do: Apply nematodes to the soil in autumn or use systemic insecticides for potted specimens.

Affects Campanula garganica

Look for: Clusters of small soft-bodied insects on new growth, causing distorted leaves.

What to do: Spray off with water or use insecticidal soap/neem oil.

Affects Campanula garganica

Look for: White, powdery fungal growth on leaves and flower buds.

What to do: Ensure good air circulation and spray with a sulphur-based fungicide if severe.

Affects Campanula garganica

Look for: Wilting, yellowing foliage despite moist soil, often in heavy or waterlogged conditions.

What to do: Plant in well-draining soil and avoid overwatering; remove affected plants promptly.

Affects Campanula garganica

Look for: Irregular holes in leaves and stems, often with silvery slime trails.

What to do: Use copper tape, beer traps, or iron phosphate-based pellets.

Affects Campbell's Magnolia · Spring

Look for: Flower buds turn brown, shrivel, and fail to open after frost.

What to do: Plant in a sheltered location away from late spring frosts.

Affects Campbell's Magnolia

Look for: Brown, crispy edges on leaves due to wind or drought stress.

What to do: Mulch well and water deeply during dry spells.

Affects Campbell's Magnolia

Look for: White, dusty fungal growth appears on leaves and young shoots.

What to do: Improve air circulation and apply a systemic fungicide if severe.

Affects Campbell's Magnolia

Look for: Irregular holes in leaves and silvery slime trails on foliage.

What to do: Use iron phosphate pellets or beer traps around the base of the plant.

Affects Campbell's Magnolia · Autumn

Look for: Notched leaf margins above ground and root damage below.

What to do: Apply systemic insecticide drench to soil in early autumn.

Affects Candelabra Aloe

Look for: White, cottony fluff appears in leaf axils and on stems.

What to do: Isolate the plant and treat infested areas with a cotton bud dipped in methylated spirit or apply insecticidal soap.

Affects Candelabra Aloe

Look for: Leaves become soft, mushy, and discoloured while the base of the plant collapses.

What to do: Ensure well-draining compost and avoid overwatering; repot in fresh mix if roots are blackened.

Affects Candelabra Aloe

Look for: Small, immobile, brown or white bumps attach firmly to leaves and stems.

What to do: Scrape off visible scales manually and spray remaining pests with horticultural oil or systemic insecticide.

Affects Candelabra Aloe · Summer

Look for: Leaves develop bleached, brown, or scorched patches after sudden exposure to intense light.

What to do: Gradually acclimate plants to brighter conditions and provide shade during peak summer sun.

Affects Candelabra Aloe

Look for: Notched edges on leaves above ground and root damage below causing wilting.

What to do: Use nematodes in the soil during warm months or apply a systemic insecticide to prevent larvae feeding.

Affects Candelabra Sage

Look for: General decline with wilting foliage and possible white fungal growth under the bark.

What to do: Remove infected plants and improve soil drainage to prevent spread to neighbouring plants.

Affects Candelabra Sage

Look for: A white, dusty fungal growth appears on leaves and stems, potentially causing distortion.

What to do: Improve air circulation and apply a suitable fungicide if infection becomes severe.

Affects Candelabra Sage · Winter

Look for: Stems become soft, mushy, and discoloured at the base, often leading to sudden collapse.

What to do: Ensure well-drained soil and avoid overwatering, especially during winter dormancy.

Affects Candelabra Sage

Look for: Lower leaves yellow and drop, followed by wilting of stems despite adequate moisture.

What to do: Avoid planting in soil previously affected by the disease and remove infected material.

Affects Candelabra Sage · Spring

Look for: Plant fails to regrow in spring due to freezing damage or waterlogged roots.

What to do: Grow in light, well-drained soil and provide mulch for protection in colder areas.

Affects Cape Cowslip · Spring

Look for: The bulb becomes soft, mushy, and may emit a foul odour while foliage wilts.

What to do: Ensure excellent drainage and keep bulbs dry during dormancy to prevent fungal infection.

Affects Cape Cowslip · Spring

Look for: Bulbs become soft, mushy, and may emit an unpleasant odour while foliage yellows.

What to do: Ensure excellent drainage in gritty compost and avoid overwatering during dormancy.

Affects Cape Cowslip

Look for: Leaf tips and margins turn brown and crispy due to low humidity or dry air.

What to do: Maintain moderate humidity and avoid placing plants near direct heat sources.

Affects Cape Cowslip

Look for: White, dusty fungal growth appears on leaves and stems in humid conditions.

What to do: Improve air circulation and treat with a suitable fungicide if severe.

Affects Cape Cowslip

Look for: A white, dusty fungal growth appears on leaves and flower stems in humid conditions.

What to do: Improve air circulation and spray with a sulphur-based fungicide if infection occurs.

Affects Cape Cowslip

Look for: Irregular holes chewed into young leaves and flower buds, often with slime trails.

What to do: Use slug pellets, beer traps, or hand-pick at night to protect tender growth.

Affects Cape Cowslip

Look for: Irregular holes are eaten in the strap-shaped leaves, often accompanied by slime trails.

What to do: Use physical barriers like copper tape or apply iron phosphate pellets around the base.

Affects Cape Cowslip · Autumn, Winter

Look for: Notched edges on leaves indicate adult feeding, while larvae damage roots underground.

What to do: Apply nematodes to the soil in autumn and winter to control root-feeding larvae.

Affects Cape Cowslip

Look for: Notched edges on leaves above ground and larvae feeding on roots underground.

What to do: Apply systemic insecticide drenches or use nematodes in the growing medium.

Affects Cappadocian Maple · Spring

Look for: Small, greenish-pink blister-like galls form on the undersides of leaves.

What to do: Usually cosmetic; severe infestations can be treated with horticultural oil in early spring.

Affects Cappadocian Maple

Look for: Browning and drying of leaf margins, often following periods of drought or transplant shock.

What to do: Water deeply during dry spells and mulch to retain soil moisture; avoid root disturbance.

Affects Cappadocian Maple

Look for: Clusters of small soft-bodied insects on new growth, causing leaf curling and sticky honeydew.

What to do: Encourage natural predators like ladybirds; use insecticidal soap for heavy infestations.

Affects Cappadocian Maple

Look for: General decline, dieback, and white fungal growth at the base of the trunk or on roots.

What to do: Ensure well-drained soil; remove infected material and avoid replanting maples in the same spot.

Affects Cappadocian Maple

Look for: Sudden wilting, yellowing, and dieback of branches or entire sections of the canopy.

What to do: Avoid planting in infected soil; remove and destroy severely affected trees to prevent spread.

Affects Cardinal Sage

Look for: Clusters of small soft-bodied insects on new growth causing distorted leaves and sticky honeydew.

What to do: Squash by hand or spray with a strong jet of water; use insecticidal soap if infestation is severe.

Affects Cardinal Sage

Look for: White powdery fungal growth on leaves and stems, often in humid conditions with poor air circulation.

What to do: Improve air circulation, avoid overhead watering, and apply a fungicide if necessary.

Affects Cardinal Sage

Look for: Wilting, yellowing leaves, and stunted growth despite adequate moisture due to waterlogged soil.

What to do: Ensure well-draining soil and avoid overwatering; repot if necessary with fresh compost.

Affects Cardinal Sage

Look for: Irregular holes chewed in leaves and silvery slime trails on foliage and soil surface.

What to do: Use physical barriers like copper tape or crushed eggshells, or apply slug pellets sparingly.

Affects Cardinal Sage

Look for: Notched leaf edges during the day and larvae feeding on roots at night, leading to plant decline.

What to do: Inspect pots regularly and use nematodes or biological controls to target larvae in the soil.

Affects Carmena's Pincushion Cactus

Look for: White, cottony masses appear in the axils and crevices of the plant body.

What to do: Isolate the plant and treat with a systemic insecticide or dab spots with alcohol-soaked cotton.

Affects Carmena's Pincushion Cactus · Winter

Look for: The stem becomes soft, mushy, and discoloured, often starting at the base.

What to do: Ensure well-draining compost and avoid overwatering, especially during the dormant winter period.

Affects Carmena's Pincushion Cactus

Look for: Small, immobile, brown or white bumps attached to the stem surface.

What to do: Remove manually with a soft brush or treat with horticultural oil or systemic insecticide.

Affects Carmena's Pincushion Cactus

Look for: Bleached, yellow, or brown patches on the side of the plant exposed to intense light.

What to do: Acclimatise gradually to bright light and avoid placing in direct midday sun initially.

Affects Carmena's Pincushion Cactus

Look for: Notches on leaf margins (if present) or sudden collapse due to root damage by grubs in compost.

What to do: Check new arrivals for grubs and use nematodes or systemic drenches as preventive control.

Affects Carrot

What to do: Sow thinly to avoid thinning out which releases scent; handle carefully to avoid bruising.

Affects Carrot

Affects Catalonian Jasmine

Look for: Clusters of small green or black insects on new growth causing distorted leaves and sticky honeydew.

What to do: Squash by hand, spray with a strong jet of water, or apply insecticidal soap if infestations are severe.

Affects Catalonian Jasmine · Spring

Look for: General decline, wilting, and dieback of shoots, sometimes with white fungal growth at the base.

What to do: Improve drainage and remove infected roots; severe cases may require removing the plant.

Affects Catalonian Jasmine

Look for: White, cottony wax secretions at leaf axils and on stems, often found in sheltered areas.

What to do: Wipe away with a cloth dampened in methylated spirit or apply insecticidal spray.

Affects Catalonian Jasmine

Look for: Small, immobile, bump-like pests attached to stems and leaves, often accompanied by sooty mould.

What to do: Scrape off small infestations manually or use systemic insecticides for larger outbreaks.

Affects Catalonian Jasmine

Look for: Fine webbing on leaves and stippled yellowing foliage, particularly in dry, warm conditions.

What to do: Increase humidity around the plant and treat with horticultural oil or a miticide if necessary.

Affects Catmint

Look for: Stems become long, weak, and floppy with sparse foliage after the first flush of flowers.

What to do: Cut back stems by half immediately after the main flowering period to encourage compact regrowth.

Affects Catmint · Summer

Look for: A white, dusty fungal growth appears on leaves and stems, particularly during dry summers.

What to do: Ensure good air circulation by thinning crowded plants and avoid overhead watering.

Affects Catmint

Look for: Plants wilt and collapse rapidly, with stems turning soft and brown near the soil line.

What to do: Plant in well-drained soil and avoid waterlogging to prevent root suffocation.

Affects Catmint

Look for: Irregular holes are chewed in young leaves and shoots, often accompanied by slimy trails.

What to do: Use physical barriers like copper tape or apply organic slug pellets around the base.

Affects Catmint

Look for: Notches appear on leaf margins and plants show sudden wilting due to root damage.

What to do: Inspect pots regularly for adult beetles at dusk and use biological nematodes in soil.

Affects Cemetery Iris

Look for: The base of the leaves and rhizome collapse, becoming soft, slimy, and foul-smelling.

What to do: Ensure excellent drainage and plant rhizomes partially exposed to prevent waterlogging.

Affects Cemetery Iris

Look for: Leaves turn black and shrivel, often starting from the base and moving upwards.

What to do: Dig up and destroy severely affected plants immediately to prevent soil contamination.

Affects Cemetery Iris · Winter

Look for: Small, circular brown or purple spots appear on the leaves, often merging into larger blotches.

What to do: Remove and dispose of infected foliage at the end of the season to reduce overwintering spores.

Affects Cemetery Iris

Look for: Orange or brown pustules develop on the leaves, causing them to yellow and wither.

What to do: Pick off lightly infected leaves early in the season to slow the spread of the fungus.

Affects Cemetery Iris

Look for: Young leaves show distorted growth, mottling, or streaking patterns.

What to do: Remove and burn infected plants as there is no cure for viral infections.

Affects Centranthus ruber

Look for: Stems become tall, weak, and floppy, requiring staking to remain upright.

What to do: Plant in full sun and cut back flower heads after first bloom to encourage bushier habit.

Affects Centranthus ruber

Look for: White powdery fungal growth appears on leaves and stems, particularly in humid conditions.

What to do: Improve air circulation by thinning dense clumps and avoid overhead watering.

Affects Centranthus ruber · Winter

Look for: Stems become soft and mushy at the base while foliage wilts despite moist soil.

What to do: Ensure planting in well-drained, gritty soil and avoid waterlogging during winter.

Affects Centranthus ruber

Look for: Irregular holes chewed into young leaves and seedlings, often accompanied by slimy trails.

What to do: Use beer traps, copper tape barriers, or organic slug pellets around vulnerable new growth.

Affects Centranthus ruber · Autumn

Look for: Notched edges on leaves above ground and root damage causing plant collapse below.

What to do: Apply biological nematodes to the soil in autumn or use systemic insecticides for potted plants.

Affects Chamomile

Look for: Clusters of small insects on new growth causing leaf curling.

What to do: Spray off with water or apply insecticidal soap.

Affects Chamomile

Look for: White powdery fungal growth on leaves and stems.

What to do: Ensure good air circulation and avoid overhead watering.

Affects Chamomile

Look for: Yellowing foliage and wilting despite moist soil conditions.

What to do: Plant in well-drained soil to prevent waterlogging.

Affects Chamomile

Look for: Irregular holes in leaves and damage to soft young shoots.

What to do: Use physical barriers like copper tape or organic slug pellets.

Affects Chelidonium majus

Look for: Clusters of small soft-bodied insects on new growth, often leaving sticky honeydew.

What to do: Encourage natural predators like ladybirds or blast off with a strong jet of water.

Affects Chelidonium majus

Look for: White, dusty fungal growth on leaves and stems, potentially causing distortion.

What to do: Improve air circulation and spray with a potassium bicarbonate solution if severe.

Affects Chelidonium majus · Winter

Look for: Yellowing foliage and general decline due to waterlogged, poorly drained soil.

What to do: Ensure well-drained soil conditions and avoid overwatering, especially in winter.

Affects Chelidonium majus

Look for: Irregular holes chewed into young leaves and stems, often accompanied by silky trails.

What to do: Use physical barriers like copper tape or organic pellets containing iron phosphate.

Affects Chelidonium majus · Summer, Autumn

Look for: Notched edges on leaves during the day and root damage causing wilting at night.

What to do: Apply biological nematodes to the soil in late summer or autumn to control larvae.

Affects Chenille Plant

Look for: Small green or black insects cluster on new growth and flower stalks, secreting honeydew.

What to do: Spray off with a strong jet of water or apply insecticidal soap to affected areas.

Affects Chenille Plant

Look for: Fine webbing on leaves accompanied by stippled, bronzed foliage and eventual leaf drop.

What to do: Increase humidity around the plant and spray with a horticultural oil or miticide if infestation is severe.

Affects Chenille Plant · Spring

Look for: Tiny white flies swarm when disturbed; leaves become sticky with honeydew and may yellow.

What to do: Use yellow sticky traps to monitor adults and treat infestations with insecticidal soap or biological controls.

Affects Chenille Plant

Look for: Leaf tips or edges turn brown and crispy due to chemical damage from tap water.

What to do: Water exclusively with rainwater or filtered water to avoid fluoride and salt buildup.

Affects Chenille Plant

Look for: White, cottony wax-like masses appear in leaf axils and on stems, often accompanied by sticky residue.

What to do: Wipe off visible bugs with a cotton bud dipped in methylated spirits and apply systemic insecticide if needed.

Affects Chenille Plant

Look for: White, cottony fluff appears in leaf axils and on stems, often accompanied by sticky residue.

What to do: Isolate the plant and treat infested areas with a cotton bud dipped in methylated spirits.

Affects Chenille Plant · Winter

Look for: Leaves turn yellow and wilt despite moist soil, often due to overwatering in winter.

What to do: Ensure pots have good drainage and water sparingly during the dormant winter period.

Affects Chenille Plant · Spring

Look for: Leaves become soft, mushy and discoloured while the stem base may blacken.

What to do: Ensure sharp drainage with gritty compost and water only when the soil is completely dry.

Affects Chenille Plant

Look for: Small, immobile, shield-like bumps on stems and leaves that secrete honeydew leading to sooty mould.

What to do: Scrape off scales manually or treat with a systemic insecticide applied as a soil drench.

Affects Chenille Plant

Look for: Semi-circular notches appear on leaf edges while roots are chewed away underground.

What to do: Use biological nematodes or systemic insecticides in the compost during active growth periods.

Affects Cherry Blossom · Autumn, Winter

Look for: Leaves turn brown, shrivel, and remain attached to the tree throughout winter.

What to do: Remove fallen leaves in autumn to reduce fungal spores for the following year.

Affects Cherry Blossom · Autumn, Winter

Look for: Leaves develop purple spots or yellow blotches and drop prematurely before autumn.

What to do: Collect and destroy fallen leaves to minimize overwintering fungal inoculum.

Affects Cherry Blossom · Spring

Look for: A white, dusty fungal growth appears on young shoots and leaves in spring.

What to do: Improve air circulation by thinning the canopy and avoid overhead watering.

Affects Cherry Blossom

Look for: Branches show silver-grey patches on the underside of leaves and dieback occurs.

What to do: Prune out infected branches well below the visible symptoms and sterilize tools.

Affects Cherry Blossom · Autumn

Look for: Notched edges on leaves above ground and root damage causing wilting below.

What to do: Apply nematodes to the soil in autumn or use physical barriers around pots.

Affects Cherry Plum

Look for: Sunken dead patches of bark with gummy ooze and small holes in leaves.

What to do: Prune out infected branches in dry weather, disinfecting tools between cuts.

Affects Cherry Plum

Look for: New growth becomes tightly curled and distorted by clusters of small black aphids.

What to do: Encourage natural predators like ladybirds or use a strong jet of water to dislodge them.

Affects Cherry Plum · Autumn, Winter

Look for: Leaves turn brown, shrivel and remain attached to the tree throughout winter.

What to do: Rake up fallen leaves in autumn to reduce fungal spores for the following year.

Affects Cherry Plum · Autumn, Winter

Look for: Leaves develop purple or yellow spots, sometimes with shotholes, and drop prematurely.

What to do: Collect and destroy fallen leaves to minimize overwintering fungal spores.

Affects Cherry Plum · Spring

Look for: A white, dusty fungal growth appears on young leaves and shoots in spring.

What to do: Improve air circulation by thinning the canopy and avoid overhead watering.

Affects Chicory

Look for: Plants send up flower stalks prematurely, resulting in bitter, tough leaves.

What to do: Sow at the correct time to avoid cold spells or extreme heat stress.

Affects Chicory

Look for: White, dusty fungal growth appears on the upper surfaces of leaves and stems.

What to do: Ensure good air circulation and spray with a fungicide or bicarbonate solution if severe.

Affects Chicory

Look for: Orange or brown pustules develop on the undersides of leaves, causing them to yellow.

What to do: Remove affected foliage immediately and avoid overhead watering to reduce humidity.

Affects Chicory

Look for: Irregular holes chewed in leaves, particularly on young seedlings and tender shoots.

What to do: Use physical barriers like copper tape or beer traps, and hand-pick at night.

Affects Chihuahua Echeveria

Look for: Clusters of small green or black insects on new growth and flower buds.

What to do: Spray with insecticidal soap or introduce natural predators like ladybirds.

Affects Chihuahua Echeveria

Look for: White, cottony fluff appears in leaf axils and on stems.

What to do: Isolate the plant and treat with a systemic insecticide or dab spots with alcohol.

Affects Chihuahua Echeveria

Look for: Leaves become soft, translucent, and mushy starting from the base.

What to do: Ensure well-draining compost and allow soil to dry out completely between waterings.

Affects Chihuahua Echeveria · Summer

Look for: Brown or bleached patches on leaves exposed to intense direct sunlight.

What to do: Acclimate plants gradually to full sun and provide shade during peak summer heat.

Affects Chihuahua Echeveria · Autumn

Look for: Notches on leaf margins during the day and root damage at night.

What to do: Apply nematodes to the soil in autumn or use a systemic granular treatment.

Affects Chinese Peony · Spring

Look for: Ants are seen crawling over flower buds, often feeding on nectar secretions rather than damaging the plant.

What to do: Leave them alone as they are generally harmless and may help deter aphids; remove only if aesthetically undesirable.

Affects Chinese Peony

Look for: Foliage collapses and turns brown, while flower buds hang down and fail to open, often showing grey mould in wet weather.

What to do: Remove and burn infected material promptly to reduce spores, and ensure good air circulation around plants.

Affects Chinese Peony

Look for: A white, dusty fungal growth appears on leaves and stems, potentially causing distortion or yellowing.

What to do: Improve air circulation, avoid overhead watering, and apply a suitable fungicide if infection is severe.

Affects Chinese Peony · Autumn

Look for: Plants appear stunted with yellowing foliage and general decline due to waterlogged soil conditions.

What to do: Ensure well-drained soil and avoid planting too deeply; lift and divide congested clumps in autumn.

Affects Chinese Peony

Look for: Irregular holes chewed into emerging shoots and leaves, often accompanied by silky trails and slime.

What to do: Use physical barriers like copper tape or apply iron phosphate-based pellets around the base of plants.

Affects Chinese Primrose

Look for: Clusters of small soft-bodied insects on new growth causing distorted leaves and sticky honeydew.

What to do: Squash by hand, spray with water, or use insecticidal soap for heavy infestations.

Affects Chinese Primrose

Look for: Large irregular holes in leaves and visible frass (droppings) on foliage.

What to do: Hand-pick caterpillars or apply biological controls like Bacillus thuringiensis.

Affects Chinese Primrose

Look for: White powdery fungal growth on leaves and stems, often in humid conditions.

What to do: Improve air circulation, avoid overhead watering, and apply a fungicide if severe.

Affects Chinese Primrose

Look for: Irregular holes chewed in leaves and silvery slime trails on foliage and soil.

What to do: Use iron phosphate pellets, beer traps, or hand-pick at night to reduce populations.

Affects Chinese Primrose

Look for: Irregular notches on leaf margins and wilting plants due to root damage by larvae.

What to do: Apply nematodes in warm soil or use biological controls like Steinernema feltiae.

Affects Chinese Wisteria · Spring

Look for: serious dieback during cold snaps, sporadic blooming due to spring frosts

Affects Chinese Wisteria

Affects Chives · Spring, Autumn

Look for: Wavy white lines in leaves; pupae in stems; distorted growth

What to do: Cover with insect-proof mesh spring and autumn; remove affected growth

Affects Chives

Look for: Pale patches and grey-purple mould on leaves in wet weather

What to do: Improve air flow; avoid overhead watering; remove infected leaves

Affects Chives

Look for: Yellowing, wilting; white fluffy fungus and black sclerotia on bulbs

What to do: No cure; lift and destroy affected plants; do not replant alliums there for years

Affects Chrysanthemum

Look for: Clusters of small soft-bodied insects sucking sap from new growth and buds.

What to do: Check plants regularly and remove pests by hand or use targeted insecticidal soap.

Affects Chrysanthemum

Look for: Small pale spots on upper leaf surface with creamy white maggots tunneling inside.

What to do: Remove affected leaves or crush larvae; use biological control nematodes in greenhouses.

Affects Chrysanthemum

Look for: White powdery fungal growth on leaves and stems, often in humid conditions.

What to do: Ensure good air circulation and avoid overhead watering to reduce humidity around foliage.

Affects Chrysanthemum

Look for: Irregular holes in leaves and damage to young shoots, especially in damp conditions.

What to do: Protect young plants with barriers or traps and maintain good garden hygiene.

Affects Chrysanthemum

Look for: Spore pustules appear on the underside of leaves, causing significant damage.

What to do: Practice good garden hygiene and remove infected growth promptly to prevent spread.

Affects Cirsium vulgare

Look for: White, dusty fungal growth on leaves in humid conditions.

What to do: Improve air circulation and avoid overhead watering to reduce humidity.

Affects Cirsium vulgare

Look for: New shoots emerge from broken root pieces left in the soil.

What to do: Dig out entire root systems carefully, ensuring no fragments remain.

Affects Cirsium vulgare

Look for: Numerous new seedlings appear in surrounding areas after flowering.

What to do: Deadhead flower heads promptly before seeds ripen to prevent spread.

Affects Cirsium vulgare

Look for: Irregular holes chewed into young leaves and seedlings.

What to do: Use physical barriers like copper tape or apply iron phosphate pellets.

Affects Cirsium vulgare

Look for: Notching on leaf margins and larvae feeding inside stems.

What to do: Tolerate as a natural biological control agent for thistle populations.

Affects Cistus bornetianus

Look for: A white, dusty fungal growth appears on leaves and stems, often causing distortion.

What to do: Improve air circulation around the plant and apply a suitable fungicide if severe.

Affects Cistus bornetianus

Look for: Leaves turn yellow and drop off while stems become soft and mushy at the base.

What to do: Ensure excellent drainage by planting in gritty, well-draining soil and avoid overwatering.

Affects Cistus bornetianus

Look for: Irregular holes are eaten in young leaves and shoots, often accompanied by slime trails.

What to do: Use physical barriers like copper tape or apply slug pellets around the base of the plant.

Affects Cistus bornetianus · Autumn

Look for: Notched edges on leaves above ground and wilting plants due to root damage below.

What to do: Apply nematodes to the soil in autumn or use systemic insecticides for potted specimens.

Affects Cistus bornetianus

Look for: Plant declines or dies during prolonged periods of cold, wet weather due to waterlogged roots.

What to do: Plant on a raised mound or in containers with sharp drainage to prevent waterlogging.

Affects Clustered Bellflower

Look for: Clusters of small soft-bodied insects on new growth, often accompanied by sticky honeydew.

What to do: Spray off with water or use insecticidal soap; encourage natural predators like ladybirds.

Affects Clustered Bellflower

Look for: White, dusty fungal growth appears on leaves and stems, often causing distortion.

What to do: Improve air circulation and water at the base; apply a fungicide if severe.

Affects Clustered Bellflower

Look for: Yellowing, wilting leaves despite moist soil, often due to poor drainage.

What to do: Ensure well-draining soil and avoid overwatering; remove affected plants if severe.

Affects Clustered Bellflower

Look for: Irregular holes in leaves and silvery slime trails on foliage and soil.

What to do: Use physical barriers, iron phosphate pellets, or hand-pick at night.

Affects Cockburn's Primrose

Look for: Clusters of small green or black insects on new growth causing distortion.

What to do: Squash by hand or use insecticidal soap for heavy infestations.

Affects Cockburn's Primrose

Look for: White, powdery fungal growth appears on leaf surfaces.

What to do: Improve air circulation and spray with a fungicide if severe.

Affects Cockburn's Primrose · Winter

Look for: Leaves turn yellow and wilt while the crown becomes soft and mushy.

What to do: Ensure excellent drainage and avoid overwatering, especially in winter.

Affects Cockburn's Primrose

Look for: Irregular holes chewed into leaves and silvery trails on foliage.

What to do: Use slug pellets or beer traps around the base of the plant.

Affects Common Alder · Spring

Look for: Leaves are skeletonised or eaten, leaving only the veins, causing significant defoliation.

What to do: Monitor for larvae in spring; severe infestations may require insecticidal treatment.

Affects Common Alder

Look for: Leaves are mined or eaten by caterpillars, leading to reduced vigour and potential suckering.

What to do: Encourage natural predators like birds; manual removal of larvae if populations are high.

Affects Common Alder

Look for: General decline in vigour with yellowing leaves, often accompanied by white fungal growth at the base.

What to do: Improve soil drainage and air circulation; remove infected roots if possible to prevent spread.

Affects Common Alder

Look for: Foliage turns brown and wilts, with dieback of branches and dark lesions forming under the bark.

What to do: Avoid waterlogged soils, ensure good drainage, and do not move infected soil or plant material.

Affects Common Alder

Look for: Irregular holes in young leaves and seedlings, with slimy trails visible on foliage.

What to do: Use physical barriers, copper tape, or approved slug pellets around young plants.

Affects Common Ash

Look for: Exit holes in the bark and sawdust-like frass, often weakening branches or killing young trees.

What to do: Maintain tree health through proper watering and mulching; prune out infested branches if detected early.

Affects Common Ash · Autumn

Look for: Diamond-shaped lesions on bark, crown dieback, and leaf loss caused by the fungus Hymenoscyphus fraxineus.

What to do: No cure exists; remove dead wood to prevent falling hazards and avoid moving infected ash material.

Affects Common Ash · Summer

Look for: Yellowing leaves in summer followed by premature leaf drop and eventual dieback of the crown.

What to do: No specific cure; focus on maintaining overall tree vigor and removing dead wood to reduce stress.

Affects Common Ash

Look for: General decline, wilting foliage, and white fungal growth at the base of the trunk or roots.

What to do: Improve drainage and soil aeration; remove severely infected trees to prevent spread to nearby plants.

Affects Common Ash

Look for: Irregular holes chewed in young leaves and seedlings, often leaving slimy trails.

What to do: Use physical barriers like copper tape or organic pellets around young plants during damp weather.

Affects Common Beech

Look for: Diamond-shaped cracks in the bark and dieback of branches caused by fungal infection entering through beetle wounds.

What to do: Remove and burn infected wood to reduce spread; maintain tree health to improve resistance as there is no cure.

Affects Common Beech · Spring

Look for: Newly emerging young leaves turn black, shrivel and die after exposure to sudden cold snaps in spring.

What to do: Plant in sheltered locations away from frost pockets; protect young trees with fleece if severe frosts are forecast.

Affects Common Beech

Look for: A white, dusty fungal growth appears on the surface of leaves and shoots, potentially causing distortion.

What to do: Improve air circulation around the tree and apply a fungicide if infection is severe.

Affects Common Beech

Look for: Wilting, yellowing foliage and stunted growth due to roots drowning in waterlogged or poorly drained soil.

What to do: Ensure planting sites have good drainage and avoid watering excessively during wet periods.

Affects Common Beech · Spring

Look for: Fluffy white patches appear on the underside of leaves in late spring, often accompanied by sticky honeydew and sooty mould.

What to do: Encourage natural predators like ladybirds; severe infestations can be treated with a systemic insecticide or horticultural oil.

Affects Common Bent

Look for: A slimy, dark green or black layer forms on the soil surface, often in damp, shaded areas.

What to do: Improve drainage and aeration by scarifying the lawn and reducing shade where possible.

Affects Common Bent

Look for: Irregular patches of dying grass caused by white C-shaped larvae feeding on roots.

What to do: Monitor for adult beetles and consider biological nematode treatments if infestation is severe.

Affects Common Bent

Look for: Small, silver-dollar-sized patches of bleached or tan grass appear on the lawn surface.

What to do: Improve air circulation by mowing regularly and avoid excessive nitrogen fertiliser in warm weather.

Affects Common Bent

Look for: Water-soaked, circular patches of grass that turn straw-coloured, often visible with morning dew.

What to do: Ensure good drainage, reduce thatch buildup, and avoid overwatering to prevent fungal growth.

Affects Common Bent · Autumn

Look for: Grass becomes loose and easily pulled up due to larvae feeding on roots underground.

What to do: Apply biological control products containing nematodes in autumn when soil temperatures are above 5°C.

Affects Common Bird's-Foot-Trefoil · Spring

Look for: Pale green or yellowing foliage indicating a lack of nitrogen or other essential nutrients.

What to do: Apply a balanced, slow-release organic fertilizer in spring if growth is stunted or discoloured.

Affects Common Bird's-Foot-Trefoil

Look for: White, dusty fungal growth appears on leaves and stems during hot, dry weather with humid nights.

What to do: Improve air circulation by thinning dense growth and avoid overhead watering to keep foliage dry.

Affects Common Bird's-Foot-Trefoil

Look for: Plants wilt and yellow despite moist soil, often due to waterlogged conditions in heavy clay.

What to do: Ensure well-drained soil by incorporating grit or planting on a raised bed if drainage is poor.

Affects Common Bird's-Foot-Trefoil

Look for: Irregular holes chewed in young leaves and stems, often accompanied by silvery slime trails.

What to do: Use beer traps, copper tape barriers, or hand-pick at night to protect emerging seedlings.

Affects Common Bird's-Foot-Trefoil · Summer

Look for: Notched edges on leaves during the day and wilting plants caused by larvae feeding on roots.

What to do: Apply nematodes to the soil in late summer or use biological controls like Steinernema carpocapsae.

Affects Common Camellia · Spring, Autumn

Look for: Flowers turn brown, shrivel and drop prematurely during spring bloom.

What to do: Rake up fallen petals immediately to remove fungal spores; choose autumn-flowering cultivars to avoid infection.

Affects Common Camellia

Look for: Individual leaves become swollen, distorted and turn white with a fungal bloom.

What to do: Pick off affected leaves before spores are released to prevent spread.

Affects Common Camellia

Look for: Leaves develop dark spots with black fruiting bodies, leading to defoliation.

What to do: Remove and destroy affected leaves promptly; improve air circulation and keep foliage dry.

Affects Common Camellia

Look for: Small, light brown scales with white egg sacs appear on leaf undersides, often accompanied by sooty mould.

What to do: Control infestations with horticultural oil or systemic insecticides; wash away sooty mould with water.

Affects Common Camellia

Look for: Raised, corky spots or patches form on the undersides of leaves due to excess water uptake.

What to do: Ensure well-draining soil and avoid overwatering; reduce humidity if grown under glass.

Affects Common Daisy

Look for: Clusters of small soft-bodied insects on new growth causing curling.

What to do: Encourage natural predators like ladybirds or spray with a strong jet of water.

Affects Common Daisy

Look for: White, dusty fungal growth on leaves and stems.

What to do: Avoid overhead watering and ensure good air circulation around plants.

Affects Common Daisy

Look for: Orange or brown pustules appear on the undersides of leaves.

What to do: Remove affected foliage and improve air circulation to reduce humidity.

Affects Common Daisy

Look for: Irregular holes in leaves and silvery slime trails on soil or plants.

What to do: Use physical barriers like copper tape or organic pellets to deter feeding.

Affects Common Daisy

Look for: Notched leaf margins and potential root damage causing plant decline.

What to do: Check roots for grubs at planting and use biological nematodes in soil.

Affects Common Dog-Violet

Look for: Fine webbing on stems and stippled, pale speckling on leaves indicating sap loss.

What to do: Increase humidity around the plant and treat with a suitable miticide if infestation persists.

Affects Common Dog-Violet

Look for: Small, dark brown or purple spots develop on leaves, sometimes causing yellowing.

What to do: Avoid overhead watering and remove infected foliage to reduce fungal spread.

Affects Common Dog-Violet

Look for: White, dusty fungal growth appears on the upper surfaces of leaves and stems.

What to do: Improve air circulation and spray with a fungicide containing myclobutanil if severe.

Affects Common Dog-Violet

Look for: Irregular holes chewed in leaves and flowers, often accompanied by silky trails.

What to do: Use physical barriers like copper tape or apply iron phosphate pellets to control populations.

Affects Common Dog-Violet

Look for: Leaves become distorted, thickened, or curled due to larval feeding inside the tissue.

What to do: Remove and destroy affected leaves immediately to prevent larvae from pupating in the soil.

Affects Common Hazel

Look for: Clusters of small soft-bodied insects suck sap from new growth, causing sticky honeydew.

What to do: Encourage natural predators like ladybirds or use a strong jet of water to dislodge them.

Affects Common Hazel · Winter

Look for: Small, wart-like swellings or galls form on leaves and stems where the mites feed.

What to do: Prune out severely affected growth in winter to reduce populations before they spread.

Affects Common Hazel · Spring

Look for: The plant declines with wilting foliage and white fungal mats may form under the bark.

What to do: Remove infected roots and replace soil, as there is no chemical cure for established infection.

Affects Common Hazel

Look for: A white, dusty fungal growth appears on leaves and shoots, potentially causing distortion.

What to do: Improve air circulation by thinning the canopy and apply a fungicide if infection is severe.

Affects Common Hazel

Look for: Leaves develop a distinctive silvery sheen on their undersides due to fungal infection.

What to do: Prune out affected branches well below the visible symptoms and burn them immediately.

Affects Common Lilac

Look for: General decline, yellowing foliage, and white fungal mats or black root-like strands at the base.

What to do: Improve drainage and remove infected plants completely to prevent spread to neighbours.

Affects Common Lilac

Look for: Angular brown spots on leaves coalesce into blackened areas, causing buds to scorch and shoots to die back.

What to do: Prune out infected growth in dry weather and avoid overhead watering to reduce spread.

Affects Common Lilac

Look for: Irregular white or brown blotches appear within the leaves as larvae tunnel through the tissue.

What to do: Remove heavily infested leaves and encourage natural predators like parasitic wasps.

Affects Common Lilac

Look for: A white, dusty fungal growth appears on leaves and young shoots, potentially causing distortion.

What to do: Ensure good air circulation by thinning the canopy and apply a suitable fungicide if severe.

Affects Common Lilac · Winter

Look for: Small, immobile, waxy scales cluster on stems and undersides of leaves, weakening the plant.

What to do: Scrape off heavy infestations by hand or use a horticultural oil spray in winter.

Affects Common Mint

Look for: Small metallic blue beetles and their larvae chew irregular holes in the foliage.

What to do: Hand-pick adults and larvae regularly; encourage natural predators like birds and ground beetles.

Affects Common Mint

Look for: Dusty orange, yellow, and black pustules appear on leaves and stems, causing shoot distortion and leaf loss.

What to do: Remove infected plants and rhizomes promptly; heat-treat healthy rhizomes in 44°C water for 10 minutes to eradicate spores.

Affects Common Mint

Look for: A white, dusty fungal growth covers the leaves and stems, potentially causing yellowing and stunted growth.

What to do: Improve air circulation, avoid overhead watering, and apply a biological fungicide if infection is severe.

Affects Common Mint · Spring

Look for: Leaves become stippled with tiny white or yellow spots and may curl or distort as feeding progresses.

What to do: Monitor plants closely and use insecticidal soap or horticultural oil for heavy infestations.

Affects Common Mint

Look for: Irregular holes chewed into leaves and stems, often accompanied by silky trails and slimy residue.

What to do: Use physical barriers like copper tape or crushed eggshells, and set out beer traps or nematodes for control.

Affects Common Primrose

Look for: A white, dusty fungal growth covers the surface of leaves and stems, potentially causing distortion.

What to do: Ensure good air circulation and avoid wetting foliage; remove severely affected parts.

Affects Common Primrose

Look for: Clusters of tiny, cup-like orange or brown spore structures appear on the undersides of leaves.

What to do: Remove and destroy infected leaves immediately to prevent spread; avoid overhead watering.

Affects Common Primrose · Winter

Look for: Leaves turn yellow or brown and wilt despite moist soil, often due to waterlogged conditions.

What to do: Plant in well-drained soil and avoid overwatering, especially during winter months.

Affects Common Primrose

Look for: Irregular holes chewed into leaves and flowers, often accompanied by silky trails and slime.

What to do: Use physical barriers like copper tape or crushed eggshells, and hand-pick pests at night.

Affects Common Primrose · Spring

Look for: Yellow spots with brown centers develop on foliage, which may drop out leaving holes in the leaves.

What to do: Improve air circulation and remove affected leaves; ensure soil is well-drained to reduce humidity.

Affects Common Sorrel

Look for: Clusters of small green or black insects on stems and leaf undersides causing curling.

What to do: Squash by hand, blast with water, or apply insecticidal soap if infestations are heavy.

Affects Common Sorrel

Look for: Leaves become tough and excessively sour as the plant sends up flower stalks.

What to do: Harvest leaves regularly and cut back flower stems before seed set to maintain quality.

Affects Common Sorrel

Look for: Small brown or black spots appearing on leaves, sometimes surrounded by yellow halos.

What to do: Remove affected leaves and avoid wetting foliage when watering to reduce spread.

Affects Common Sorrel

Look for: White, dusty fungal growth on leaves and stems, often in humid conditions.

What to do: Improve air circulation and spray with a bicarbonate of soda solution or fungicide.

Affects Common Sorrel

Look for: Irregular holes chewed in young leaves and silky slime trails on foliage.

What to do: Use copper tape barriers, beer traps, or iron phosphate pellets to control populations.

Affects Common Teasel

Look for: Clusters of small green or black insects on new growth causing leaf curling and sticky honeydew.

What to do: Squash by hand, blast off with water, or apply a plant-based insecticide if infestations are severe.

Affects Common Teasel

Look for: White powdery fungal growth on leaves and stems, often in humid or stagnant air conditions.

What to do: Improve air circulation and spray with a bicarbonate of soda solution or approved fungicide.

Affects Common Teasel

Look for: Irregular holes chewed in young leaves and silvery slime trails on foliage and stems.

What to do: Use beer traps, copper tape barriers, or iron phosphate-based pellets to protect seedlings.

Affects Common Teasel

Look for: Lower stems become soft, brown, and mushy, causing the plant to collapse in wet conditions.

What to do: Ensure well-drained soil and avoid overwatering; remove affected plants to prevent spread.

Affects Common Teasel · Autumn

Look for: Notched edges on leaves during the day and root damage causing wilting in potted plants.

What to do: Apply nematodes to the soil in autumn or use systemic insecticides for severe infestations.

Affects Common Thyme

Look for: Seedlings collapse and rot at the base due to fungal infection in damp conditions.

What to do: Use free-draining seed compost, avoid overwatering, and ensure good air circulation.

Affects Common Thyme

Look for: A white, dusty fungal growth appears on leaves and stems, often in humid conditions.

What to do: Ensure good air circulation by pruning and avoid wetting foliage when watering.

Affects Common Thyme

Look for: Foliage turns yellow or brown and wilts despite moist soil due to waterlogged roots.

What to do: Plant in well-drained soil and avoid heavy mulching around the crown.

Affects Common Thyme

Look for: Irregular holes chewed into young shoots and leaves, with slimy trails visible.

What to do: Use physical barriers like copper tape or organic slug pellets around new plants.

Affects Common Thyme · Winter

Look for: Stems turn brown and brittle during wet, cold winters due to poor drainage.

What to do: Site in full sun with excellent drainage and avoid planting in heavy clay soils.

Affects Coneflower

Look for: White powdery fungal growth appears on leaves and stems, often in humid conditions.

What to do: Improve air circulation and avoid overhead watering; remove affected foliage.

Affects Coneflower · Autumn, Winter

Look for: Plants collapse and die back, particularly in winter on wet or heavy soils.

What to do: Ensure well-drained soil and avoid autumn planting to prevent waterlogging.

Affects Coneflower

Look for: Irregular holes chewed into young leaves and seedlings, often with slime trails.

What to do: Use physical barriers like copper tape or organic slug pellets around new plants.

Affects Coneflower

Look for: Tall stems bend or break under the weight of flowers, especially in shade.

What to do: Plant in full sun and stake tall varieties if necessary to support blooms.

Affects Conophytum flavum

Look for: Small green or black insects cluster on new growth and flower buds, secreting sticky honeydew.

What to do: Isolate affected plants and treat with a systemic insecticide or strong jet of water.

Affects Conophytum flavum

Look for: White, cottony wax-like masses appear in leaf fissures and at the base of the plant.

What to do: Apply alcohol-dipped cotton buds to remove pests or use a suitable insecticidal spray.

Affects Conophytum flavum

Look for: Plants appear swollen, translucent or prone to splitting before rotting sets in.

What to do: Strictly withhold water during dormancy periods and ensure pots have adequate drainage holes.

Affects Conophytum flavum

Look for: Bodies become soft, mushy and discoloured, often collapsing entirely.

What to do: Ensure excellent drainage with gritty compost and water only when the soil is completely dry.

Affects Conophytum flavum · Summer

Look for: Leaves develop bleached, brown or scorched patches due to sudden intense light exposure.

What to do: Acclimatise plants gradually to full sun and avoid placing them in direct midday summer heat initially.

Affects Cootamundra Wattle · Winter

Look for: Small, immobile, fluted brown scales attached to stems and leaves, weakening the plant.

What to do: Prune out heavily infested branches and treat remaining pests with horticultural oil in winter.

Affects Cootamundra Wattle

Look for: Fine webbing and stippled, yellowing leaves caused by tiny mites feeding on foliage.

What to do: Increase humidity around the plant and spray with a horticultural oil or insecticidal soap.

Affects Cootamundra Wattle · Spring

Look for: Wilting foliage, dieback of branches, and white fungal growth under the bark at the base.

What to do: Improve drainage and remove infected roots; severe cases may require removing the plant.

Affects Cootamundra Wattle

Look for: White, cottony wax-like masses found in leaf axils and on stems, often accompanied by sticky honeydew.

What to do: Wipe off infestations with a cloth dampened in methylated spirit or apply systemic insecticide.

Affects Cootamundra Wattle

Look for: Notched leaf margins on young plants and root damage caused by grubs in the compost.

What to do: Check pots for grubs before planting and use nematodes or systemic insecticides as a preventative.

Affects Copper Iris

Look for: Rhizomes become mushy, blackened, and emit a foul odour, causing the plant to collapse.

What to do: Ensure excellent drainage and avoid waterlogging; remove and destroy infected rhizomes immediately.

Affects Copper Iris

Look for: Fuzzy grey fungal growth on leaves and flowers, particularly in humid or damp conditions.

What to do: Improve air circulation around plants and remove dead foliage to reduce humidity at the base.

Affects Copper Iris

Look for: Small, water-soaked spots on leaves that turn brown with yellow halos, eventually causing leaves to die back.

What to do: Remove and dispose of infected leaves; avoid wetting foliage when watering.

Affects Copper Iris

Look for: Leaves are skeletonised or completely defoliated by green, slug-like caterpillars.

What to do: Hand-pick larvae into soapy water or apply a biological control like nematodes.

Affects Copper Iris

Look for: Irregular holes chewed in leaves and flowers, often accompanied by silky trails.

What to do: Use physical barriers like copper tape or hand-pick at night; avoid excessive mulch near crowns.

Affects Coral Bells · Winter

Look for: Plants are pushed out of the soil by freezing ground, exposing roots to drying winds.

What to do: Mound soil around exposed roots in winter and ensure planting in well-drained locations.

Affects Coral Bells · Spring, Autumn, Winter

Look for: Orange-brown pustules on leaves that may turn brown, shrivel, or develop a shot-hole appearance.

What to do: Remove infected foliage and old leaves in autumn to reduce overwintering spores.

Affects Coral Bells

Look for: Pale or light-coloured foliage turns brown and crispy at the edges due to excessive sun exposure.

What to do: Plant in dappled shade and water regularly during dry spells to prevent stress.

Affects Coral Bells

Look for: Adults chew notches in leaf edges while larvae feed on roots, causing wilting and collapse.

What to do: Cover pot compost with gravel to prevent egg-laying and treat with nematodes or systemic insecticides.

Affects Coriander

Look for: similar to other food allergies

Affects Cornflower

Look for: Clusters of small soft-bodied insects on new growth, often leaving sticky honeydew.

What to do: Encourage natural predators like ladybirds or blast off with a strong jet of water.

Affects Cornflower

Look for: White, dusty fungal growth appears on leaves and stems, potentially causing distortion.

What to do: Ensure good air circulation and avoid overhead watering; remove severely affected foliage.

Affects Cornflower

Look for: Plants wilt and collapse despite moist soil due to waterlogged, poorly drained conditions.

What to do: Plant in well-drained soil and avoid overwatering to prevent fungal attack on roots.

Affects Cornflower

Look for: Irregular holes chewed in young leaves and seedlings, often accompanied by slimy trails.

What to do: Use physical barriers like copper tape or organic pellets to protect vulnerable young plants.

Affects Cornflower

Look for: Notched edges on leaves above ground and wilting due to root damage below soil level.

What to do: Check potted seedlings for grubs and apply biological nematodes or systemic controls if found.

Affects Corrugated Sage

Look for: Plant decline with white fungal growth under bark and black fan-shaped fruiting bodies at base.

What to do: Excavate and remove infected roots and soil; replant only after thorough cleanup.

Affects Corrugated Sage

Look for: White, dusty fungal growth appears on leaves and stems, potentially causing distortion.

What to do: Improve air circulation and apply a suitable fungicide if infection is severe.

Affects Corrugated Sage · Winter

Look for: Leaves turn yellow or brown and wilt despite moist soil due to waterlogged roots.

What to do: Ensure well-drained soil and avoid overwatering, especially in winter.

Affects Corrugated Sage

Look for: Irregular holes in leaves and silvery slime trails on foliage and surrounding soil.

What to do: Use physical barriers, copper tape, or approved slug pellets to protect young growth.

Affects Corrugated Sage · Spring

Look for: Lower leaves yellow and drop off while upper foliage may show wilting or stunting.

What to do: Remove and destroy infected plants to prevent spread; do not compost.

Affects Corsican Crocus

Look for: Flowers stripped of petals or corms dug up from the soil surface by foraging birds.

What to do: Plant under low shrubs or use netting to protect emerging flowers and shallow-planted corms.

Affects Corsican Crocus · Summer

Look for: Soft, mushy corms with a foul smell, often accompanied by yellowing or failing foliage.

What to do: Ensure sharp drainage and keep completely dry during summer dormancy to prevent fungal attack.

Affects Corsican Crocus

Look for: White, dusty fungal growth on leaves and flower stems, potentially causing distortion.

What to do: Improve air circulation and apply a fungicide if severe, though often cosmetic on crocuses.

Affects Corsican Crocus

Look for: Irregular holes chewed in emerging leaves and flowers, often with slimy trails visible.

What to do: Use slug pellets, beer traps, or hand-pick at night to protect tender new growth.

Affects Corsican Crocus · Autumn

Look for: Notched leaf margins on seedlings and root damage causing sudden wilting or collapse.

What to do: Check pots for grubs before planting and use biological nematodes or chemical controls in autumn.

Affects Courgette

Look for: Grey, fluffy growth on plants.

What to do: Cut out any affected areas and remove any dead growth on the ground. Avoid splashing the leaves when watering.

Affects Courgette

What to do: Prune out and destroy affected leaves immediately.

Affects Cow Parsley

Look for: Clusters of small soft-bodied insects on new growth, accompanied by sticky honeydew.

What to do: Spray with a strong jet of water or use insecticidal soap/neem oil.

Affects Cow Parsley

Look for: White powdery fungal growth on leaves and stems, causing yellowing and distortion.

What to do: Improve air circulation, avoid overhead watering, and apply a fungicide if severe.

Affects Cow Parsley

Look for: Wilting and yellowing leaves despite moist soil, often with a foul smell from the base.

What to do: Ensure well-draining soil and avoid overwatering; remove affected plants.

Affects Cow Parsley

Look for: Irregular holes chewed in leaves and stems, often with silvery slime trails.

What to do: Use beer traps, copper tape barriers, or iron phosphate-based pellets.

Affects Cowslip

Look for: A white, dusty fungal growth covers the upper surfaces of leaves and stems.

What to do: Improve air circulation around plants and avoid overhead watering to keep foliage dry.

Affects Cowslip

Look for: Clusters of tiny, cup-like orange or brown spore-producing structures appear on the undersides of leaves.

What to do: Remove and destroy infected leaves immediately; avoid fungicides to protect biodiversity.

Affects Cowslip · Winter

Look for: Leaves turn yellow and wilt despite adequate moisture, often due to waterlogged soil.

What to do: Ensure well-drained soil and avoid overwatering, especially in winter.

Affects Cowslip

Look for: Irregular holes chewed in young leaves and flower buds, often accompanied by slimy trails.

What to do: Use physical barriers like copper tape or beer traps, and hand-pick at night.

Affects Cowslip · Summer

Look for: Notched edges on leaves above ground, while grubs feed on roots underground causing wilting.

What to do: Check pots for grubs before planting and use nematode treatments in late summer.

Affects Crab Apple · Spring

Look for: Young shoots become curled and sticky with honeydew, which may lead to sooty mould growth.

What to do: Encourage natural predators like ladybirds or use a horticultural oil spray in early spring.

Affects Crab Apple

Look for: Sunken, discoloured lesions appear on branches and trunk, sometimes oozing sap.

What to do: Cut out infected wood well into healthy tissue and disinfect tools between cuts.

Affects Crab Apple · Autumn

Look for: Leaves develop greenish-black spots and blotches, often leading to early leaf drop.

What to do: Rake up fallen leaves in autumn and apply a fungicide spray at bud burst if severe.

Affects Crab Apple

Look for: A white powdery growth appears on young leaves and shoots, potentially reducing tree vigour.

What to do: Prune to improve air circulation and apply a suitable fungicide at bud burst.

Affects Crab Apple · Spring, Autumn, Winter

Look for: Caterpillars eat leaves, blossoms, and young fruitlets between bud burst and late May.

What to do: Fit tree bands in autumn to trap egg-laying moths or apply a dormant oil spray.

Affects Crab Apple

Look for: Lumpy outgrowths on the bark are covered with a white, fluffy waxy substance.

What to do: Scrape off infested areas and apply horticultural oil or systemic insecticide if severe.

Affects Crataegus laevigata

Look for: Clusters of small soft-bodied insects on new growth causing leaf curling and sticky honeydew.

What to do: Encourage natural predators like ladybirds or use a strong jet of water to dislodge them.

Affects Crataegus laevigata

Look for: Irregular holes chewed in leaves, often with visible frass or webbing.

What to do: Hand-pick caterpillars if few; use biological controls like nematodes for larger infestations.

Affects Crataegus laevigata

Look for: Shoots and branches appear scorched or blackened with leaves clinging to the stem.

What to do: Prune out infected wood well below visible symptoms during dry weather, disinfecting tools between cuts.

Affects Crataegus laevigata · Spring, Winter

Look for: Small, wart-like swellings or galls forming on leaves and stems.

What to do: Prune out affected growth in winter; severe infestations may require horticultural oil spray.

Affects Crataegus laevigata · Spring

Look for: General decline, wilting foliage, and white fungal growth at the base of the trunk.

What to do: Improve drainage and avoid deep planting; severe cases may require removal to prevent spread.

Affects Crimean Iris

Look for: Small, yellowish spots with purple borders develop on leaves, eventually turning brown.

What to do: Remove affected leaves and improve air circulation; apply fungicide if infection persists.

Affects Crimean Iris

Look for: White, powdery fungal growth appears on leaves and stems, potentially causing distortion.

What to do: Improve air circulation and apply a fungicide if severe; avoid wetting foliage when watering.

Affects Crimean Iris

Look for: Irregular holes chewed into leaves and flowers, with slimy trails visible on foliage.

What to do: Use slug pellets, beer traps, or hand-pick at night to protect emerging shoots.

Affects Crimean Iris

Look for: Bulbs become mushy, discoloured and emit a foul odour, often following waterlogging.

What to do: Ensure excellent drainage in sandy soil and avoid overwatering; remove infected bulbs immediately.

Affects Crimean Iris · Autumn

Look for: Notched edges on leaves above ground and root damage causing wilting below ground.

What to do: Apply nematode treatments in autumn or use systemic insecticides for potted plants.

Affects Crocosmia

Look for: Plants show poor growth with yellowing leaves and soft, decaying corms.

What to do: Ensure well-drained soil and discard any damaged or rotting corms when dividing.

Affects Crocosmia

Look for: Small brown spots appear on the leaves and occasionally on the flowers.

What to do: Improve air circulation by dividing clumps and avoid planting in shaded, damp positions.

Affects Crocosmia

Look for: Fine webbing is visible on foliage, often accompanied by stippled or discoloured leaves.

What to do: Keep plants well-watered to reduce stress and spray with water or horticultural oil if infested.

Affects Crocosmia · Spring

Look for: Irregular holes are eaten in the emerging shoots and young leaves in spring.

What to do: Use slug pellets, copper tape barriers, or hand-pick pests at night to protect new growth.

Affects Crocus

Look for: Flowers stripped of petals or corms dug up and scattered by foraging birds.

What to do: Use netting or bird deterrents over planting areas during flowering season.

Affects Crocus

Look for: Soft, mushy corms with a foul smell, often leading to failure to flower or plant collapse.

What to do: Ensure well-drained soil and avoid waterlogging; discard infected corms immediately.

Affects Crocus

Look for: Irregular holes chewed into emerging leaves and flowers, often accompanied by slimy trails.

What to do: Use slug pellets, beer traps, or copper tape barriers to protect tender new growth.

Affects Crocus

Look for: Black, powdery fungal growth on leaves resulting from honeydew secreted by aphids.

What to do: Control aphid populations and wash leaves with water to remove the mould.

Affects Crocus · Autumn

Look for: Notched leaf margins on seedlings or wilting plants caused by grubs feeding on roots underground.

What to do: Check pots for grubs before planting and use biological nematodes or chemical controls in autumn.

Affects Crocus biflorus · Spring

Look for: Bulbs become soft, mushy, and may emit a foul odor; plants fail to emerge.

What to do: Ensure well-drained soil and avoid waterlogging during storage and planting.

Affects Crocus biflorus

Look for: Irregular holes in leaves and flowers, with slimy trails visible on foliage.

What to do: Use iron phosphate pellets or beer traps around the planting area.

Affects Crocus biflorus

Look for: Bulbs are dug up from the soil and eaten or displaced by foraging squirrels.

What to do: Plant bulbs in wire mesh baskets or use repellents to deter digging.

Affects Crocus biflorus · Autumn

Look for: Notched leaf margins above ground and root damage below ground causing wilting.

What to do: Apply nematodes to soil in autumn or use systemic insecticides on bulbs.

Affects Crocus ligusticus

Look for: Corms become soft, mushy, and discoloured, often with a foul smell, leading to plant failure.

What to do: Ensure well-drained soil and avoid waterlogging; store lifted corms in a dry, airy place.

Affects Crocus ligusticus

Look for: A white, powdery fungal growth appears on leaves and stems, potentially stunting growth.

What to do: Improve air circulation around plants and treat with a sulphur-based fungicide if necessary.

Affects Crocus ligusticus

Look for: Corms dug up and eaten from the ground or containers, leaving bare patches.

What to do: Plant corms deep enough or use wire mesh barriers to protect them from digging animals.

Affects Crocus ligusticus

Look for: Irregular holes chewed in emerging leaves and flowers, often accompanied by slimy trails.

What to do: Use physical barriers like copper tape or crushed eggshells, or apply iron phosphate-based pellets.

Affects Crocus ligusticus · Summer

Look for: Semi-circular notches on leaf margins from adults; sudden wilting and collapse due to larval root damage.

What to do: Apply biological nematodes (Steinernema feltiae) to the soil in late summer or use chemical drenches for potted plants.

Affects Crocus longiflorus

Look for: Clusters of small insects on new growth causing leaf distortion and sticky honeydew.

What to do: Encourage natural predators like ladybirds or use insecticidal soap for severe infestations.

Affects Crocus longiflorus · Summer

Look for: Corms become soft, mushy, and discoloured, often causing the plant to fail to emerge.

What to do: Ensure well-drained soil and keep corms completely dry during summer dormancy.

Affects Crocus longiflorus

Look for: Corms dug up and eaten from the soil, leaving empty holes in the planting area.

What to do: Plant corms in wire mesh baskets or use physical barriers to deter digging animals.

Affects Crocus longiflorus

Look for: Irregular holes chewed into leaves and flowers, often accompanied by slimy trails.

What to do: Use slug pellets, beer traps, or copper tape barriers to protect emerging foliage.

Affects Crocus longiflorus · Summer

Look for: Irregular notches on leaf margins and sudden wilting due to larvae destroying the corm roots.

What to do: Apply nematode biological controls in late summer or use chemical drenches for container-grown plants.

Affects Crocus Tulip · Spring

Look for: Bulbs become soft, mushy, and may emit a foul odour due to waterlogged soil.

What to do: Ensure sharp drainage by planting in gritty compost or well-drained gravel beds.

Affects Crocus Tulip

Look for: Irregular holes chewed into emerging leaves, flower buds, and young shoots.

What to do: Use slug pellets, beer traps, or copper tape barriers around planting areas.

Affects Crocus Tulip · Autumn

Look for: Bulbs are dug up from the soil and eaten, leaving empty holes in the garden.

What to do: Plant bulbs in wire mesh baskets or use netting to protect them during autumn planting.

Affects Crocus Tulip · Spring

Look for: Yellow streaks on leaves that turn brown, and flowers may become distorted or fail to open.

What to do: Remove and destroy infected bulbs immediately; avoid reusing contaminated soil.

Affects Crocus Tulip · Autumn

Look for: Notched edges on foliage above ground and larvae feeding on roots underground.

What to do: Apply nematodes to the soil in autumn or use systemic insecticides as a preventative measure.

Affects Crown Cactus

Look for: White, cottony wax-like masses appear in crevices and around areoles.

What to do: Isolate the plant and treat with a systemic insecticide or dab spots with alcohol-soaked cotton.

Affects Crown Cactus

Look for: Small white cottony masses appear in crevices, on spines, or at the base of the plant.

What to do: Remove pests manually with a cotton bud dipped in methylated spirits or apply insecticidal soap.

Affects Crown Cactus · Winter

Look for: Stems become soft, mushy, and discoloured, often starting at the base.

What to do: Ensure excellent drainage and keep the plant almost completely dry during winter dormancy.

Affects Crown Cactus

Look for: The stem becomes soft, mushy, and discoloured, often starting at the base where it meets the soil.

What to do: Ensure excellent drainage with gritty compost and allow the soil to dry completely between waterings.

Affects Crown Cactus

Look for: Fine webbing and tiny moving specks are visible, often accompanied by stippled or yellowing tissue.

What to do: Increase humidity around the plant and treat with a suitable miticide or insecticidal soap.

Affects Crown Cactus

Look for: Fine webbing and stippled, yellowing foliage indicating dry indoor conditions.

What to do: Increase humidity around the plant and spray with water or use a miticide if infestation is severe.

Affects Crown Cactus · Summer

Look for: Patches of bleached, white, or brown necrotic tissue appear on the side facing direct light.

What to do: Acclimate plants gradually to brighter light and provide shade during intense midday summer sun.

Affects Crown Cactus

Look for: White or brown bleached patches on stems exposed to sudden intense sunlight.

What to do: Acclimatise gradually to brighter light and avoid placing in direct midday sun initially.

Affects Crown Cactus

Look for: Semi-circular notches on leaf margins (if present) or sudden collapse due to root damage.

What to do: Use biological nematodes in the soil during warm months or apply a systemic granular treatment.

Affects Crown Cactus

Look for: Semi-circular notches are chewed into the edges of leaves, while larvae damage roots underground.

What to do: Use nematodes in the soil during warmer months or apply a systemic insecticide to prevent root loss.

Affects Cypripedium Gabriela

Look for: Brown, crispy patches on leaves caused by intense sun exposure.

What to do: Provide dappled shade or move to a location protected from midday sun.

Affects Cypripedium Gabriela

Look for: White powdery fungal growth appears on leaf surfaces.

What to do: Improve air circulation and treat with a sulphur-based fungicide if severe.

Affects Cypripedium Gabriela

Look for: Leaves turn yellow and wilt while the crown becomes soft and mushy.

What to do: Ensure excellent drainage with gritty compost and avoid waterlogging.

Affects Cypripedium Gabriela

Look for: Irregular holes chewed in leaves and seedlings, often with slime trails.

What to do: Use iron phosphate pellets or beer traps to reduce populations.

Affects Cypripedium Gabriela · Autumn

Look for: Notched leaf margins during the day and damaged roots underground.

What to do: Apply nematodes in autumn or use systemic insecticides on potted plants.

Affects Cypripedium hank

Look for: White powdery fungal growth on leaf surfaces causing distortion.

What to do: Improve air circulation and apply a suitable fungicide if severe.

Affects Cypripedium hank

Look for: Leaves turn yellow and wilt despite moist soil; roots appear mushy.

What to do: Ensure excellent drainage with gritty compost and avoid overwatering.

Affects Cypripedium hank

Look for: Irregular holes chewed in leaves or seedlings eaten entirely.

What to do: Use slug pellets, copper tape barriers, or hand-pick at night.

Affects Cypripedium hank · Autumn

Look for: Notches on leaf margins during the day; larvae damage roots at night.

What to do: Apply nematodes to soil in autumn or use biological controls.

Affects Cypripedium hybrid

Look for: Browning or yellowing of leaf edges indicating exposure to too much direct sunlight.

What to do: Relocate plants to partial shade or dappled light conditions, especially during hot spells.

Affects Cypripedium hybrid

Look for: White powdery fungal growth on leaves, causing distortion and premature leaf drop.

What to do: Improve air circulation around plants and apply a suitable fungicide if infection becomes severe.

Affects Cypripedium hybrid · Winter

Look for: Yellowing, softening leaves and general decline due to waterlogged soil conditions.

What to do: Ensure excellent drainage using gritty compost mixes and avoid overwatering during winter dormancy.

Affects Cypripedium hybrid · Spring

Look for: Irregular holes chewed into new shoots and young leaves, often causing severe damage in spring.

What to do: Protect emerging shoots with physical barriers or use slug pellets sparingly around the base of plants.

Affects Cypripedium hybrid · Autumn

Look for: Notched leaf margins on foliage and root damage leading to wilting, particularly in potted specimens.

What to do: Apply systemic insecticide drenches or biological controls like nematodes to the compost in early autumn.

Affects Daffodils

Look for: Plants produce healthy green foliage but fail to produce any flower stems or blooms.

What to do: Lift and divide overcrowded clumps every few years and ensure adequate sunlight and nutrients.

Affects Daffodils

Look for: Bulbs develop a soft, brown rot at the base, causing foliage to yellow and collapse.

What to do: Ensure well-drained soil and avoid waterlogging; remove and discard infected bulbs promptly.

Affects Daffodils

Look for: Bulbs become soft and rot from within, often containing a maggot and muddy excrement.

What to do: Dig up affected bulbs immediately to destroy larvae and dispose of them in household waste.

Affects Daffodils

Look for: Yellow streaks running down the leaves and distorted flowers with white flecks or streaks.

What to do: Remove and destroy infected plants as there is no cure; source virus-free stock for new plantings.

Affects Daffodils

Look for: Irregular holes eaten into emerging foliage and flower buds, often accompanied by slime trails.

What to do: Use physical barriers like copper tape or apply iron phosphate-based slug pellets around plants.

Affects Dahlia variabilis

Look for: Grey mould on flowers and stems, leading to rotting buds and foliage.

What to do: Deadhead regularly and avoid wetting foliage when watering.

Affects Dahlia variabilis

Look for: White, dusty fungal growth on leaves and stems, causing distortion.

What to do: Ensure good air circulation and apply a fungicide if severe; resistant varieties help.

Affects Dahlia variabilis

Look for: Irregular holes in leaves and flowers, often accompanied by slimy trails.

What to do: Use physical barriers, iron phosphate pellets, or hand-pick at night.

Affects Dahlia variabilis

Look for: Soft, mushy tubers with a foul smell during storage or after planting.

What to do: Store tubers in dry, frost-free conditions and ensure well-drained soil.

Affects Dahlia variabilis

Look for: Notched leaf margins and wilting plants caused by grubs feeding on roots.

What to do: Check pots for grubs before planting and use biological nematodes or chemical controls.

Affects Dalmatian Cranesbill

Look for: Clusters of small green or black insects on new growth, often accompanied by sticky honeydew.

What to do: Spray off with a strong jet of water or treat with insecticidal soap or natural predators.

Affects Dalmatian Cranesbill

Look for: Small brown or black spots develop on leaves, sometimes surrounded by yellow halos.

What to do: Remove infected leaves and avoid wetting foliage when watering to prevent spread.

Affects Dalmatian Cranesbill

Look for: A white, dusty fungal growth appears on leaves and stems, often causing distortion.

What to do: Improve air circulation and apply a fungicide or bicarbonate spray at first sign.

Affects Dalmatian Cranesbill

Look for: Stems become soft and mushy near the base while foliage wilts despite moist soil.

What to do: Ensure well-draining compost and avoid overwatering; remove affected plants immediately.

Affects Dalmatian Cranesbill

Look for: Irregular holes chewed in foliage and silvery slime trails left on leaves and soil.

What to do: Use iron phosphate pellets, beer traps, or hand-pick at night to reduce populations.

Affects Daphne arbuscula

Look for: Clusters of small soft-bodied insects on new growth causing leaf curling.

What to do: Squash by hand or spray with a horticultural oil or insecticidal soap.

Affects Daphne arbuscula

Look for: Distinct dark spots appear on the foliage, potentially leading to defoliation.

What to do: Improve air circulation and remove affected leaves to reduce spore spread.

Affects Daphne arbuscula

Look for: General decline with white fungal growth at the base of the stem.

What to do: Remove infected plants entirely as this disease is difficult to treat.

Affects Daphne arbuscula

Look for: The plant wilts and dies back rapidly, often with darkened roots.

What to do: Ensure excellent drainage and avoid waterlogging to prevent fungal infection.

Affects Daphne arbuscula

Look for: Slow growth or dieback after planting due to sensitive root system.

What to do: Plant carefully in well-drained soil and avoid transplanting once established.

Affects Daphne Rhododendron · Spring

Look for: Silver or bleached patches on the upper leaf surface with black specks underneath.

What to do: Encourage natural predators like ladybirds or use a horticultural oil spray in spring.

Affects Daphne Rhododendron

Look for: White, dusty fungal growth on leaves and shoots, potentially causing distortion.

What to do: Improve air circulation and apply a fungicide if infection is heavy; avoid overhead watering.

Affects Daphne Rhododendron · Winter

Look for: Flower buds turn brown, shrivel, and fail to open, often dropping prematurely.

What to do: Remove affected buds and apply a copper-based fungicide in late winter before bud swell.

Affects Daphne Rhododendron

Look for: General decline, yellowing foliage, and wilting despite moist soil conditions.

What to do: Ensure excellent drainage and avoid waterlogging; remove severely affected plants.

Affects Daphne Rhododendron · Autumn

Look for: Notched leaf margins and wilting or death of plants due to root feeding by larvae.

What to do: Apply biological nematodes in autumn or use systemic insecticides for severe infestations.

Affects Darley Dale Heath · Spring

Look for: Flower buds fail to open or turn black and drop before blooming.

What to do: Apply a systemic insecticide like dimethoate in early spring if infestation is severe.

Affects Darley Dale Heath · Spring

Look for: Leaves turn pale green or yellow due to lack of iron or nitrogen.

What to do: Apply ericaceous fertiliser in spring and avoid using lime-based soils or water.

Affects Darley Dale Heath

Look for: A white, dusty fungal growth appears on the leaves and stems.

What to do: Improve air circulation and spray with a fungicide containing myclobutanil if necessary.

Affects Darley Dale Heath

Look for: Foliage turns brown and drops off while the soil remains persistently wet.

What to do: Ensure excellent drainage by planting in gritty, acidic compost and avoid overwatering.

Affects Darley Dale Heath

Look for: Fine webbing between leaves and stippled, yellowing foliage during hot, dry weather.

What to do: Wash plants with water to dislodge mites or use a horticultural oil spray.

Affects Daurian Rhododendron · Spring

Look for: Flower buds turn brown and shrivel before opening, often following late spring frosts.

What to do: Site plants in sheltered locations away from cold drafts to protect developing buds.

Affects Daurian Rhododendron

Look for: Small brown or black spots develop on leaves, sometimes surrounded by yellow halos.

What to do: Remove affected foliage and avoid wetting leaves when watering to reduce humidity.

Affects Daurian Rhododendron

Look for: White powdery fungal growth appears on leaves and stems, potentially causing distortion.

What to do: Improve air circulation around the plant and apply a suitable fungicide if severe.

Affects Daurian Rhododendron

Look for: Irregular holes chewed in young leaves and shoots, often accompanied by slime trails.

What to do: Use slug pellets, beer traps, or hand-pick pests at night to protect new growth.