Nymania capensis grows simple leaves, spirally arranged or tufted on dwarf spur-branchlets with short petioles. They are oblong, lanceolate or oblanceolate in shape with rounded tips and tapering bases. The leathery, dark green blades are hairless, the midribs sometimes visible, either in pale colour, protruding ridge or both. The leaf dimensions are from 8 mm to 45 mm long, and from 2 mm to 7 mm wide.
The flowers, pink to scarlet, are sometimes less noticed than the colourful inflated fruit capsules appearing side by side in this picture. The flowers have overlapping petals forming cylindrical corolla tubes with slight bell-shaped bulges. The colourful fruits are inflated and four-angled.
Flowering occurs mainly in spring or early summer, but usually after rain (Vlok and Schutte-Vlok, 2015; Coates Palgrave, 2002; iNaturalist).