Physocarpus opulifolius · Shrub
Honey fungus: Improve drainage and avoid planting in soil previously infected; remove affected plants carefully to prevent spread.
Chlorosis: Apply ericaceous compost or chelated iron fertiliser to correct nutrient availability in high-pH soils.
Powdery mildew: Ensure good air circulation by thinning dense growth and water at the base to keep foliage dry.
Slugs and snails: Use physical barriers like copper tape or apply organic slug pellets around the base of the shrub.
Vine weevil: Apply systemic insecticide drenches or biological controls like nematodes to the soil.