It grows as a glandular, thornless shrub which can reach 5 or 6 m (16 or 20 ft) in height and spread to twice that in width. It is somewhat variable in morphology. The leaves are made up of many hairy, oval-shaped, spine-tipped leaflets. The inflorescence is a spike-shaped raceme of many flowers, each with a single purple petal and ten protruding stamens with yellow anthers. The fruit is a legume pod containing one or two seeds.