A much branched succulent shrublet up to 200 mm high forming rounded spreading clusters up to 200 mm in diameter. The leaves are very fragile, variable in shape and size, mainly inversely egg-shaped to almost orbicular, 10-25 ×10-25 mm, very swollen after rain, becoming somewhat flattened (dorsiventrally compressed) during drought; the upper surface is flat to rounded (convex) and the lower surface rounded. The leaf margins are reddish in the upper part and the surface grey-green with spreading, to recurved hairs. The leaf base is wedge-shaped and the apex is blunt (obtuse)

The flowers are small and arranged in an elongated inflorescence 40-100 mm long bearing few to many flower clusters (dichasia). The inflorescence stalk is hairy and purplish at the base. The floral calyx has triangular to spear-shaped (lanceolate) lobes 1 mm long. The flowers are small, without a flower stalk, about 4×2 mm, the petals 3×1.3 mm, white and spreading. Its stamens have brownish anthers (pollen bearing part). Crassula sericea var. sericea flowers mainly during Winter (May-August).