Erect, perennial, much branched herb or undershrub, 45–100(–150 or more) cm tall, scabrid; stems usually branched above with branches ascending, densely pubescent with pubescence usually in 3 or 4 rows alternating with leaf insertions. Leaves usually in whorls of 3–4, undivided or rarely 3-fid, linear to linear-lanceolate, 15–30(–50) mm long, 1–3.5(–7) mm wide, margins revolute, strigose to scabrid, midrib very prominent. Inflorescence usually terminal, racemose, many-flowered, up to 20(–35) cm long; flowers in whorls of 3–4, frequently closely arranged; bracteoles linear to linear-lanceolate, 2.5–5 mm long, arising 0.3–0.5 mm below base of calyx, long-pubescent to hispid-strigose or subglabrous; pedicels 1.5–4.5 mm long, increasing to 6.5 mm in fruit. Calyx 3.5–4 mm long, increasing to 6.5 mm in fruit, 10-ribbed, shortly scabrid-pubescent; lobes deltate, ± 1.5 mm long, densely tomentose at margins and inside. Corolla pink to lilac or lavender, or occasionally purplish, 7–8 mm long; limb broadly ovoid to subglobose, 9–13.5 mm in diameter, emarginate, glabrous. Fertile anther cells oblong, 2.8–3 mm long. Capsule ovoid to subglobose, 4–5 mm long, 3–3.5 mm in diameter, retuse, glabrous.
