The breeding season is from March to October. There are at least 2 generations per year, possibly up to 6, with the last brood hibernating as an adult. The female lays over 1,000 eggs, laying them in clusters of 20 to 45 on the underside of the food plant's leaves. The eggs are oval in shape, and are cream to yellow, turning orange prior to hatching. After about 3 to 6 days, the larva hatches from the egg. It varies in color from greenish gray to dark brown. Its body is segmented, and will reach a length of 8 mm. Young larvae will drop to the ground if disturbed while feeding, while older larvae secrete a substance which repels competitors from eating the food plant's leaves. After three instars, the larva pupates in a burrow about 2cm underground. The adult emerges 6 to 9 days later. Adults create holes around 1cm in diameter in leaves. Flies strongly.