Ceanothus

Ceanothus is a genus of about 50-60 species of shrubs or small trees in the Buckthorn family Rhamnaceae. The genus is confined to North America, with the center of its distribution in California; many of the species there are known as California-lilac, but unsurprisingly, the species found elsewhere have other common names. In garden use, most are simply called by their Latin names.

The majority of the species are evergreen, but the handful of species adapted to cold winters are deciduous. The leaves are opposite or alternate (depending on species), small (typically 1-5cm long), simple, and mostly with serrated margins. The flowers are white, blue, pale purple or pink, maturing into a dry, three-lobed seed capsule.

Many species are popular garden ornamentals, and dozens of hybrids and cultivars have been selected.