Two generations from late May to early August and early August to September. A usually pale-green moth although the colour often fades to whitish-green with age.

Individuals from the second generation are smaller and darker. The hooked forewing tip has a reddish tinge and a white line runs across the fore and hind wings.

The adults may often be disturbed from rest where they sit on the underside of tree and shrub leaves. The larvae can be seen from mid-August to the following May or June, spending the winter lying flat against the stems of the foodplant.