Currant blister aphid (Cryptomyzus ribis). The yellow-green Currant blister aphid has a round shape and is the causative agent of red “blisters” on the leaves of currants. White, red and black-currants can all be affected. In severe infestation, the leaves yellow and shrivel. The Currant blister aphid secretes honeydew that makes leaves, berries and branches sticky. Sooty dew easily forms on the honeydew.
The Currant blister aphid overwinters as an egg on the branches of currants.
Lacewings, ladybird, parasitoid wasps and hover flies are among the natural enemies of the Currant blister aphid.
Where to find
- Red, white and black currants
- Stachys species
Control
Difficult to to control; as soon as the red blisters become visible, the harm is already done and the currant is covered in honeydew. Cut away infested leaves.
Prevention
Maintain natural enemies by omitting spraying with insecticides. Keep the area around the currants free of herbaceous plants.
