Erect to ascending, slender succulent annual or short-lived perennial, branching above the base; stems up to 15(–28) cm high, rather stiffly ascending. Leaves alternate, spaced, linear-terete, 9–25 mm long, 1–2 mm wide, sharply acute; axillary hairs in long shaggy tufts, sometimes indistinct, each axil also with 2 longer, brownish, hair-like scales with falcately-curving bases (these sometimes indistinct). Flowers in terminal clusters of 3–6 or more, encircled by ± 8 involucral leaves enclosing dense woolly hairs, opening in the morning; involucral leaves longer than the cauline leaves, very variable in length, up to 30 mm long, slightly to much exceeding the flower cluster, spreading, finally slightly downturned. Sepals 3–4.5 mm long, rounded on the back, keeled towards the acute apex with a slight crest; petals 5, usually bright red, occasionally orange-red, rose-pink or rarely yellow, 2.5–8 mm long, obovate-oblong, obtuse to acute; stamens (5–)8–13(–19); stigma (3–)4–5-branched. Capsule 5 mm long, 2.5 mm in in diameter, dehiscing below the middle, lid a conical or rounded dome about as wide as high; seeds 0.5–0.75 mm long, metallic grey or occasionally silvery, the testa cells jigsaw-shaped to stellate, convex to conical.