Blackberries: Pests & Diseases
Garden blackberries are vigorous, productive brambles that suit a sunny boundary or training along strong wires. Modern thornless varieties make picking easier, but still need regular tying-in and pruning. Good spacing, firm support and prompt removal of old fruited canes help keep berries clean and healthy through the often damp British summer.
Common pests
Birds are the most obvious pest once berries darken, with blackbirds and thrushes often taking fruit before it is fully ripe. Raspberry beetle larvae can occur in berries, particularly where raspberries grow nearby. Aphids cluster on tender shoot tips and may spread viruses. Slugs and snails spoil low fruit, while vine weevil may damage roots of container-grown blackberries and notch the leaves.
Common diseases
Cane diseases, including spur blight, cane blight and cane spot, can produce dark patches, cracking and dieback. Grey mould rots tightly packed berries in wet weather, often starting on damaged fruit. Purple blotch causes purplish marks on leaves and canes and may reduce vigour. Viruses can lead to mottled foliage, poor growth and reduced cropping, especially in plants raised from unreliable stock.
Prevention
Plant healthy named varieties in a sunny, open site and train shoots along wires to keep a clear framework. Leave room between plants for air to move through the canopy. Remove weeds and old fruit from around the base, water at soil level, and avoid working among plants when foliage is wet. Use clean secateurs and remove old fruited canes after harvest rather than leaving them through winter.
Non-chemical control
Cover ripening fruit with secure bird netting, checking daily that no wildlife is trapped. Pick regularly and remove soft, mouldy or slug-damaged berries. Hand-remove aphid colonies from shoot tips or rinse them away, while planting nectar-rich flowers nearby helps hoverflies and ladybirds. Cut diseased canes down to healthy wood or their base. Biological nematodes can be used against vine weevil larvae in suitably warm, moist compost or soil.
What to look for
From spring, inspect new shoots for aphids, leaf notches and unusual mottling. Check tied-in canes for dark lesions or dieback. As berries form, look twice weekly for raspberry beetle larvae, bird damage, slugs and grey mould. After the final harvest, identify and remove every cane that has fruited.
Tips
Blackberries ripen over several weeks, so pick only fully black, easily released fruit. Wear gloves even with thornless cultivars, as old growth can still be rough. Keep new shoots separate from fruiting canes to make pruning quicker and improve airflow.
Blackberries pests & diseases: frequently asked questions
What are the common pests of blackberries?
Birds are the most obvious pest once berries darken, with blackbirds and thrushes often taking fruit before it is fully ripe.
What diseases affect blackberries?
Cane diseases, including spur blight, cane blight and cane spot, can produce dark patches, cracking and dieback.
How do I prevent pests and diseases on blackberries?
Plant healthy named varieties in a sunny, open site and train shoots along wires to keep a clear framework.
General guidance for UK home gardens, focused on prevention and non-chemical control. The RHS or a local garden centre can help with tricky cases. Page updated 18 Sep 2026.