Corolla lilac, mauve, blue, reddish or white, tube (2)3.5–6 mm. long, filiform, glabrous, lobes 2–2.5 x 0.5–0.8 mm., lanceolate, usually hairy outside; filaments c. 1.5–2.5 mm. long, glabrous, anthers c. 1 mm. long; style (3)5–8 mm. stigma lobes 1-1.5 mm. long; ovary c. 1 x 0.6–0.8 mm., densely hairy.
Leaves decussate, often pseudo-verdcillate; blades (10)15–90 x 2–20(22) mm., ovate to lanceolate to linear-lanceolate, glabrous to densely hairy, particularly above; petioles 0–8 mm. long; stipular sheath with 3–4 setae, c. 1–3 mm. long.
Calyx: enlarged, foliaceous lobe c. 3–5 x 1-2 mm., lanceolate, margins usually hairy, setiform lobes small or minute, unequal, densely hairy.
Stems c. 15–100 cm. long, slender, ± much-branched, densely hairy above, glabrescent below or rarely subglabrous.
Seed blackish, c. 1.4–1.6 x 0.8 mm., ovoid, dorsal side convex, slightly keeled, ventral side flat
Inflorescence many-flowered, spike-like, to c. 25 cm. long when in fruit.
Fruit yellowish brown to dark purplish brown; mericarps 2 x 0.7–0.9 mm.
Annual or rarely perennial herb or subshrub, erect or straggling.
Bud with limb abruptly expanded into an ovoid head.