Recognise currant blister aphid

3rd June 2020

The foliage of red, white and blackcurrants can show strange raised red blisters, or curled and distorted greenish-yellow shoot tips. Damage is caused by a sap-sucking aphid that hatches on the currant in spring, feeding on the lower leaf surface, flies to another plant in midsummer, then returns in autumn to lay overwintering eggs.