Zanthoxylum is a genus of about 250 species of deciduous and evergreen trees and shrubs in the citrus or rue family, Rutaceae, native to warm temperate and subtropical areas worldwide. Common names also include Prickly-ash and Hercules’ Club. The fruit of several species are used to make the spice Sichuan pepper. They are also used as bonsai trees. Historically, the bark was widely used for toothache, colic, and rheumatism.

Zanthoxylum capense, commonly known as Small Knobwood, will grow to be 4 to 7m tall if planted in open ground but it’s size can be easily controlled in a pot and treated as a bonsai specimen. It has thorny grey bark and the crushed leaves & seeds give off a very pleasing citrus oil smell. It has small greenish-white flowers in sprays during summer followed by brownish-red fruit.