Corn earworm eggs are pin-head sized and has characteristic ridges. They are laid singly by female moths and turn from white to dark brown before hatching in 3 to 10 days. Larval development takes about 18 days before they pupate in the soil and remain for about 8-14 days. Development from egg to adult takes 3 to 4 weeks during the summer. There are several generations per year.
Caterpillars have chewing mouthparts.
Adults have siphoning mouths. The newly hatched caterpillar will eat its egg shell and then feed on tender leaves. Older caterpillars feed on older leaves and tunnel into fruit. Caterpillars have silk glands and produce silk threads around feeding sites. They also leave excrement in and underneath feeding sites.