Didierea madagascariensis (Baill.1880) Initially formed by a single candle-like stem, it eventually branches and develops a tree-like form, capable of reaching up to 8 meters in height. It is densely covered with spines, which are irregular in shape and often branched. The leaves are somewhat fleshy and elongated. Flowering is very abundant, though the flowers are small and light in color. It does not tolerate cold. It requires moderate watering and well-drained soil. Etymology: With reference to it originating from Madagascar.Place of Origin: Madagascar, near the southern coast on sandy soils.
Didierea trollii (Capuron & Rauh1961) It has a shrubby growth habit and can spread over a large area, though it typically does not exceed 50 cm in height. In its initial stage, the young stems grow almost prostrate, later giving rise to thicker, upright stems. The plant consists of cylindrical stems with small tubercles, each topped by a cluster of very sharp spines accompanied by several small, narrow, oval leaves, which fall off in summer if temperatures are sufficiently high. It is not cold-tolerant. Etymology: In honor of Wilhelm Troll (1897–1978), professor of botany.Place of Origin: Madagascar, southwestern island thorn forest.