The stems of Crassula macowaniana are much-branched, bare below the newer leaves remaining clustered at stem tips. The stems spread, some partly prostrate. Old stems are pale grey and woody, roughly gnarled from earlier leaf loss and some flaking.
The inflorescences are rounded to flat-topped and many-flowered, up to 7 cm in diameter. They are positioned over but close to the leaves, the stalks 1 cm to 5 cm long with spaced, small stem leaves.
The small, waxy, star-shaped flowers are white, sometimes tinged pinkish red; the five pointed petals spreading. The five stamens have short, thin, white filaments and dark globose anthers around the bulging ovary in the flower centre.
Flowering happens from spring to early summer (Frandsen, 2017; Williamson, 2010; Le Roux, et al, 2005; Bond and Goldblatt, 1984; iNaturalist).