Herb with annual stems 1–2 m tall from a perennial short woody rootstock; stems erect, hardly branched, pale green or purplish, ridged, shortly ascending-scabrid with simple hairs, ± glabrescent. Leaves sessile or shortly petiolate, elliptic to linear, 4–17 cm long, 0.4–4.4 cm wide, the upper smaller, base cuneate to truncate or cordate, margins slightly revolute, serrate or subentire, apex acute and apiculate to acuminate and aristate, scabrid above, hispidulous beneath especially on veins, with dense sessile glands. Capitula numerous in compound terminal corymbiform cymes, often rather crowded; involucre cylindric or ovoid, 5–10 mm long, 4–15 mm in diameter, occasionally subtended by tiny leaves; phyllaries 3–4-seriate, often purplish especially in upper part, erect or sometimes ± recurving at the apices, 2–10 mm long, lanceolate or triangular-lanceolate, acute or attenuate, the inner obtuse, all pungent, thinly arachnoid-pubescent. Florets many (± 50); corolla purple, purplish blue or mauve, 7–9 mm long, lobes 1.5–3 mm long, glabrous or with a few stiff apical hairs, glandular. Achenes cylindric, about 2.5 mm long, 10-ribbed, ascending-pubescent; outer pappus scale-like, 0.5–1.2 mm long, inner pappus 3.5–5.5 mm long, tawny.
