Annual or perennial herb. Stem usually branched, jointed, flattened to winged, 10–60 cm high, 1–3 mm wide. Leaves 5–20 cm long, 2–5 mm wide. Inflorescence with primary bracts narrowly ovate, sub-equal, 1.5–5 cm long. Perianth 10–20 mm diam., white to cream-coloured with purple-brown or blue throat; lobes oblong, acute to acuminate, usually sparsely glandular-pilose externally; staminal filaments 2–3 mm long, almost completely united; anthers c. 1.5 mm long; ovary 1–2 mm diam., glabrous or glandular-pilose. Capsule (3–)4–6 mm diam., brown; seeds angular, c. 1 mm diam., dark brown. Flowers Oct.–Feb.(–Apr.).
Wim, GleP, VVP, VRiv, MuF, GipP, OtP, WaP, Gold, CVU, GGr, DunT, NIS, EGL, EGU, WPro, HSF, HNF, OtR, Strz, VAlp. Also naturalised WA, SA, Qld, NSW. Native to Mexico and South America. A weed of gardens, roadsides and other disturbed areas.
