English lavender

Lavandula angustifolia, commonly called English lavender, is an evergreen subshrub in the mint family (Lamiaceae), native to dry, sunny slopes of the western Mediterranean. It is the classic English garden lavender: small, bushy, intensely fragrant, with narrow grey-green leaves and spikes of small violet-blue flowers in midsummer. English lavender is prized for its scent, its tolerance of poor dry soils, and its attraction to bees and other pollinators.

Lavandula angustifolia is a small, bushy subshrub with a woody base and soft, cushion-shaped young growth. The narrow leaves are grey-green and aromatic; crushed leaves release the characteristic lavender scent. In midsummer it sends up slender unbranched stems topped with short, dense flower spikes of small two-lipped violet flowers. Mature plants reach 60 to 90 cm tall and spread about as wide. Foliage is evergreen in mild winters, semi-evergreen in cold ones.

Lavender performs best in full sun, in poor to moderately fertile, free-draining soil — chalk, loam or sand are all fine, with a neutral to alkaline pH. Wet, heavy or acidic soil is the most common cause of failure, especially in winter. Once established, lavender is highly drought-tolerant and needs little supplementary watering. Avoid mulching right up to the crown; an open, sunny position with free air movement reduces the risk of fungal problems.

Plant container-grown specimens in spring or early autumn, spacing them 45 to 60 cm apart for a low hedge or 60 to 90 cm apart as specimen plants. Water in well for the first season; after that, lavender is self-sufficient in most UK summers. Trim lightly after flowering — into the current season’s growth, never into old bare wood — to keep plants compact and well-shaped. A hard renovation prune rarely succeeds; replace old, leggy plants rather than trying to restore them.

The most frequent problem is winter die-back caused by cold, wet conditions at the crown, often aggravated by planting in heavy soil or mulching right up to the stems. Rosemary beetle (Chrysolina americana) is the principal insect pest; check plants in late winter and pick off the metallic green and purple beetles by hand. Grey mould (Botrytis) can damage flower spikes in wet summers; improve air movement by spacing plants properly. Cuckoo spit (the larva of the froghopper Philaenus spumarius) appears in late spring but is harmless.

Several cultivars of Lavandula angustifolia are widely available from UK nurseries and are reliably hardy in all but the coldest gardens: ‘Hidcote’ (AGM) is the classic compact dark-violet hedge lavender, 60 cm; ‘Munstead’ (AGM) flowers earlier and stays smaller at 45 cm; ‘Alba’ is a white-flowered cultivar to 75 cm useful for contrast; ‘Rosea’ has unusual soft-pink flowers but is slightly less vigorous. For gardens on heavy or acid soil, the hybrid Lavandula × intermedia cultivars (such as ‘Grosso’) are more tolerant but flower later and lack the clean English scent.