As with a number of other succulent plant families, the essentially cosmopolitan (absent from Australia and much of South America), Crassulaceae is centred in South Africa where under a great variety of conditions it has diversified and adapted to form what is now one of the most represented families of the South African succulent flora. It is in fact the world's third largest succulent family following Cactaceae and Aizoaceae. Crassulaceae are dicotyledonous (the embryo of the plant has two cotyledons/seed leaves) plants belonging to the order Rosales. The family consists of ± 34 genera with ± 1 500 species.

World-wide, the genus Sedum is the largest in the family with some 428 species (Van Jaarsveld & Koutnik 2004). In southern Africa there are five genera, namely Adromischus, Crassula, Tylecodon, Cotyledon and Kalanchoe. The largest genus here is Crassula with about 150 species.

According to Toelken (1977), Hermann was the first to illustrate any South African species of Crassula in 1687. Linnaeus recognized 28 species by the end of his life in 1753. Thereafter the numbers of species increased rapidly. The majority were added by Thunberg in1778. During the early part of the nineteenth century, Haworth not only described new species but also subdivided the genus into several sections.

Practically all are succulents, in fact, the family name Crassulaceae and genus Crassula are derived from the Latin, crassus which means fat or thick and mostly refers to the succulent leaves and stems associated with most members of the family. The species name arborescens is the Latin name for tree-like, alluding to the relatively large, tree-like appearance of this particular plant.