The plants are perennials, forming compact, rosulate, basal clusters, when in flower up to 250 mm tall, and 200 mm in diameter. The roots are fibrous. The stems erect to decumbent, succulent, glabrous, terete, up to 8 mm in diameter, yellowish green at first, becoming reddish brown with age. The leaves are sessile, firm, distinctly succulent, linear-triangular, 40–160 × 8–12 mm; adaxial surface flat to slightly channelled, lower surface rounded, yellowish to reddish green. The leaf margin is entire with a pointed leaf tip (apex acute), and bearing a short point (mucro). The inflorescence is a terminal, round-topped thyrse with many pedicellate, 5-merous flowers in 1–many dichasia; basal part of inflorescence without hairs (glabrous), the upper parts with scattered, recurved, scabrid hairs; bracts triangular-subulate, becoming smaller distally; basal bracts 10 × 4 mm, distal bracts 4 × 1.5 mm; pedicels 7–25 mm long. The sepals are triangular, 4 × 1.5 mm, surface subglabrous, with scattered recurved translucent scabrid hairs, with distinct marginal cilia; apex acute. The petals triangular, 5 × 1.8 mm, spreading, slightly recurved at tip; apex reddish with distinct subulate dorsal appendage, 0.5 mm long. The stamens 5 × 0.8 mm, tapering towards apex; anthers 0.8 × 0.5 mm, brown; pollen yellow. The fruits are carpels tapering into subulate styles. Flowering time is in summer and autumn (January–March).

Fig. 2. An illustration of Crassula smithii by Vicki Thomas, from a plant grown at Kirstenbosch National Botanical Garden, in the Succulent Collection.