Barberry is a large genus of deciduous and evergreen shrubs from 1–5 m (3.3–16.4 ft) tall, found throughout temperate and subtropical regions of the world (apart from Australia). Species diversity is greatest in South America and Asia; Europe, Africa and North America have native species as well.

The genus Barberry has dimorphic shoots: long shoots which form the structure of the plant, and short shoots only 1–2 mm (0.039–0.079 in) long. The leaves on long shoots are non-photosynthetic, developed into one to three or more spines:96 3–30 mm (0.12–1.18 in) long. The bud in the axil of each thorn-leaf then develops a short shoot with several normal, photosynthetic leaves.