Twining annual or perennial with a thickened, sometimes almost tuberous taproot, stems ascending to c. 50 cm, simple or few-branched. Leaves all basal or within lower few cm of stems, linear to narrowly obovate or clavate, the largest 1.5–6 cm long, 2–10 mm wide, sessile, glabrous. Flowers rather distant on flexuose, twining scapes; bracts mostly opposite; pedicels typically 3–5 mm long at anthesis, elongating to c. 1 cm or more and up-curved in fruit; sepals broadly ovate or obovate, 2–3.5 mm long, broadly rounded or truncate, persistent; petals 5, 5–6 mm long, pale pink; stamens 5–8; style trifid to base. Capsule narrowly ovoid, 4.5–7.5 mm long, pale, splitting almost to base into 3 valves; seeds c. 30–40, c. reniform, 0.5–0.7 mm long, dark brown, papillate in close regular rows. Flowers Sep.–Oct.