Stem up to 60 cm. high, erect, simple or branched from the base, puberulous (hairs very short and thin, arcuate, antrorse, subappressed) and sparsely setose (setae c. 0·5 mm. long, yellowish towards the apex, brownish at the swollen base).
Flowers (4)5–9 per raceme; peduncles up to 25 cm. long, sparsely hairy at the base, glabrous upwards; pedicels c. 2 mm. long in flower, up to 4 mm. long in fruit.
Petals c. 22 mm. long, orange, attenuate-cuneate towards the base, adnate to the calyx-tube for 3·5 mm., the limb c. 9 × 5 mm., rhombic-obovate.
Calyx sparsely setose, without hairs; tube 10 mm. long; lobes 5 mm. long, oblong-linear, acute, with a brown seta below the apex.
Brevistylous flowers: filaments of the longer stamens ±12 mm. long, those of the shorter ones ± 9 mm. long; anthers 3 mm. long.
Capsules up to 5·5 × 0·15 cm., glabrous.
Ovary 3 mm. long; styles 3 mm. long.
Seeds 2·25–3 × 1–1·25 mm.
Flower-buds acute.
Annual herb.