Advice
RHS Help & Advice
Capsid bugs (mainly Lygocoris pabulinus and Lygus rugulipennis)
Plants affected
Many outdoor ornamental plants including Caryopteris, Chrysanthemum, Clematis, Dahlia, Forsythia, Fuchsia, Hydrangea, Magnolia, Phygelius, roses and Salvia. Fruits and vegetables can also suffer damage, in particular apples, bush fruit, potatoes and beans.
The healthy fuchsia on the right highlights the contrast with its damaged neighbour.
Symptoms
Signs of damage appear from late May to September. The leaves near the shoot tips have many small, brown-edged holes. Affected flower buds, particularly those of fuchsia, may fail to develop, or open unevenly in the case of chrysanthemum, dahlia and other daisy-like flowers.
Apple capsid bug (Plesiocoris rugicollis) damages the foliage as described above. It also feeds on the young fruitlets, which results in bumps or raised corky scabs developing on the mature fruit. These blemishes are only skin deep and do not affect the eating and keeping qualities of the fruits.
Cause
Capsid bugs suck sap mainly from the shoot tips and buds of many plants. As they feed they secrete a toxic saliva into the plants which kills cells immediately around the feeding area. When the leaves expand from the buds, the dead areas tear into many small holes.
The adult bugs are up to 6mm long and have distinctive wings: the basal two-thirds are coloured and thickened, the outer third is transparent. The wings are folded flat over the body when at rest, so the transparent part of the wings shows as a clear diamond-shaped area at the rear end of the insect.
Control
Inspect the shoot tips of susceptible plants from mid-May onwards. If capsids bugs or signs of damage are seen, spray with bifenthrin (Bayer Sprayday Greenfly Killer Plus, Doff All-In-One Garden Pest Killer, Bayer Bug-Free or Scotts Bug Clear Gun). Apples can be sprayed shortly after the flowers have fallen. Vegetables generally tolerate capsid damage and do not need spraying for this pest.