Variable, perennial succulent with a thick, usually bottle-shaped, twisted, greyish brown caudex, often more than 1m long and tapering to a many-branched tip. Upright, succulent brown branches produce ovate, grey-green leaves, to 10cm long. Red, pink, or white flowers, to 4-6cm across, are borne in small terminal corymbs throughout summer, sometimes before the leaves. Height 1.5m, Spread 1m. East to South-West Africa, Arabian Peninsula.