Eggs are laid in several batches of 50-100 eggs on the upper surface of leaves during June and July. The egg mass is covered with a wax-like secretion that so closely matches the green colour of the leaf that detection is difficult. Hatching occurs within 17-23 days.
Larvae disperse after hatching and, while young, each one lives in a silken web placed beside the midrib on the underside of a leaf. The new generation larvae may cause further damage to the apple fruit before they hibernate. Larvae taken into apple stores can even continue to feed on the fruit. Some of the larvae of the new generation hibernates after moulting once or twice; others develop to maturity and give rise to a second generation of moths in September and early October. The moths hibernate as young larvae in cocoons fixed to twigs or buds. These emerge in spring over a fairly long period from late March to early May.
Pupation occurs in late May to early June inside leaves that have been spun together by the larvae. The adult moths appear mid-June and are found until mid-August. The greatest numbers appear in late June or July, dependent on weather (Andrew et al., 1997).