Perennial aromatic herb.  Stems erect or ascending, 30-90 cm long, branched, glabrous; leaves lanceolate, acute, blade punctate; flowers in large terminal spikes, 2.5-7.5 cm long, the ones at the sides being longer than the one in the middle, calyx glabrous, with acute teeth, usually ciliate; corolla purple, rarely white, glabrous.

The typical botanical description may vary due to the existence of varieties within the species.

Biennial or perennial herb with a strong smell, sparsely branched, glabrous, 30 cm to 1 m high. Longitudinally striated stem. Alternate leaves, 3 to 25 cm long, petioles with a sheathing base, composed of a few leaflets with a deeply lobed or dentate margin; the upper leaves are smaller than the lower ones and are short petiolate or subsessile. Umbels composed of 6 to 16 small almost sessile umbels or on short peduncles, less than 1.5 cm long.