Pea moth: how to recognise and treat it

Pest

Symptoms

When shelling, one or two creamy-white caterpillars up to 14 mm long with dark dots are found eating into the peas.
Piles of caterpillar droppings (frass) lie next to the damaged peas.
Attacked pods may turn yellow and ripen early.

Cover the peas with fleece or insect-proof mesh while they flower in June–July so the moths cannot lay eggs; peas pollinate themselves, so the crop is not affected.
Where needed, spray Bacillus thuringiensis var. kurstaki, spinosad or pyrethrins at the newly hatched caterpillars before they enter the pods — about 10–15 days after moths start appearing steadily in a pheromone trap; follow the label.
Clear or dig in spent plants before the caterpillars leave the dry pods, and dig over the soil to destroy overwintering caterpillars.

The RHS advises gardeners against insecticides for pea moth; where they are registered for home use, pyrethroids such as zeta-cypermethrin or esfenvalerate are timed like the sprays above — follow the label dose and pre-harvest interval.

Reference information, not a guarantee. Read and follow the label of any product: dose, safety and the days to wait before harvest.

Sow quick-maturing varieties early or late so they flower outside the June–July egg-laying period.
Grow mangetout — the pods are eaten before the seeds develop, so they escape damage.
Remove wild vetches near the plot; they are also hosts.
Hang a pheromone trap from May to see when the moths are flying.

Figures checked against these sources.