The succulent leaves of Crassula campestris grow opposite, densely overlapping and stalkless on the soft stems. Leaf-shape is narrowly ovate to triangular, a little blunt-tipped unlike the flower petals. The leaf colour is green, pale green or dull yellow, sometimes somewhat seasonally reddened.

The small, yellowish flowers grow in great numbers in small, dense clusters from most leaf axils, seeming stalkless. The five petals of every flower are acutely pointed, attenuating like little spines or thistle-like, especially when they dry out.

Flowering happens from late winter to spring (Privett and Lutzeyer, 2010; Bond and Goldblatt, 1984; iNaturalist).