Annual, 20-120 cm tall from a taproot, hispidulous or scabrous and sparsely hispid throughout; inflorescence densely short-pubescent, hispid. Stems ascending to erect, branched or simple. Basal leaves oblong-oval to ovate, 6-20 x 3-15 cm, pinnate, oblong to lanceolate divisions pinnatifid or incised, petiole usually much shorter than blade; cauline leaves like basal but shorter-petiolate or sessile. Flowers numerous, short-pedicellate in dense, corymbosely branched, approximate, pedunculate cymes; cymes 4-12 cm long, erect in fruit. Calyx-lobes linear to linear-lanceolate, 4-6 x 0.3-1 mm, acute, densely pubescent, hispid, scarcely enlarged in fruit. Corolla bluish purple, broadly campanulate, tardily deciduous, 7-10 x 7-10 mm, lobes oval, 2.5-3 mm long, the whole longer than calyx. Stamens exserted, 9-14 mm long; filaments glabrous, anthers oblong-ovoid, c. 0.75 mm long; scales usually wholly adnate, Capsule broadly ovoid, 3-4 mm long, obtuse, hispidulous at apex; seeds usually 2, oblong 2-3 mm long, dark brown, coarsely rugose. Fl. 7.
Native of U.S.A. . Planted elsewhere for bee fodder and as an ornamental.