At first this plant was thought to be a form of Crassula multicava, but in fact differs from it in several ways, the main one being that the guttation glands which form pits on the leaf surfaces only occur along the margins of the leaves in Crassula streyi and are not scattered on the surfaces. The broadly elliptic succulent leaves are dark glossy green on the top, while the under surface is maroon to carmine giving it a striking appearance. Some forms have attractive white spots along the veins on the upper surface of the leaf. The leaves become longer as they age. It is a relatively slow growing perennial to 350 mm tall, but is usually shorter as the stems tend to sprawl and lose the lower leaves as get older. The lax stems sometimes send down roots. The dainty terminal sprays of greenish yellow flowers are tinged red and borne in May and June.