Overwintering eggs are embedded in Scotch broom stems beneath a waxy cap. Tiny nymphs (<2 mm long) hatch in early spring and gather near new leaf buds. Nymphs vary from whitish to orange to gray. They feed primarily along the stem, rarely on the leaves themselves. Nymphs grow through five instars before developing into brown or grayish, aphid-like adults 2–3 mm long with clear wings. Adults feed on new growth of Scotch broom, lay eggs, and die by early summer. There is one generation per year.