[3][4] It is the largest member of the California lilacs (the Ceanothus genus), and is characterized with glossy, dark green foliage that is adorned by pale blue to white flowers in bloom.

[6] Ceanothus arboreus is a spreading bush growing up to 12–36 feet (3.7–11.0 m) in height.

[7] It has large, glossy, dark green leaves which are leathery or felt-like on their undersides.

[7] Its showy bright blue flowers grow in plentiful panicles, or bunches, of tiny five-lobed blossoms.

[3]'Ceanothus arboreus is cultivated as an ornamental plant for use in drought tolerant and wildlife gardens and natural landscaping projects.