Crassula rupestris is a much-branched, succulent, perennial subshrub, up to 12 inches (30 cm) tall and wide (up to 3 feet/1 m tall in nature). The stems are thin, fleshy near the growing tip, but rather woody lower down. Leaves are small, thick, opposite, ovate and lanceolate in shape, up to 1 inch (2.5 cm) long and grayish in color (during the summer months the leaf margins turn a brilliant red or yellow). Crassula rupestris var. monticola is a wonderful variety with slightly smaller, thick, rounded leaves. Flowers are grouped in clusters, deep pink to pale pink, star-shaped and up to 0.25 inch (6 mm) across.