Forsythia is a genus of flowering plants in the family Oleaceae (olive family). There are about 11 species, mostly native to eastern Asia, but one native to southeastern Europe.
They are deciduous shrubs typically growing to a height of 1–3 m (3–9 ft.) and, rarely, up to 6 m (18 ft.), with rough grey-brown bark. The leaves are opposite, usually simple but sometimes trifoliate with a basal pair of small leaflets, and range from 2–10 cm (1–4 in.) in length and, rarely, up to 15 cm (6 in.) long; the margin is serrated or entire.
The flowers are produced in the early spring before the leaves, bright yellow with a deeply four-lobed corolla, the petals joined only at the base. These become pendant in rainy weather thus shielding the reproductive parts.