Crassula atropurpurea is a succulent shrublet, its branched stems may be woody low down. The leaves are paddle-shaped, sometimes finely hairy. They may be green or greyish green with margins red and cartilaginous.

Variability associated with the plant's distribution from Namaqualand to the Eastern Cape is confirmed by the existence of six recognised variaties.

The height achieved is rarely as tall as 60 cm, much of it contributed by the tall flower panicles (Bond and Goldblatt, 1984; Manning, 2007; Smith, et al, 1997).