Stems: branched, rough-hairy. Leaves: ovate-lanceolate, serrate, pubescent, especially beneath. Flowers: calyx slightly curved, very hairy in the throat, corolla elongated, two lipped, lips linear, somewhat equal, the upper erect, entire or slightly notched, the lower spreading, three lobed at the apex, its lateral lobes ovate, obtuse, the middle one narrowed and slightly notched.

The Wild Bergamot is an aromatic plant with thin, ovate-lanceolate, pointed leaves, toothed at the edges and rounded at the base. The dense flower clusters which are magenta, purplish, lavender, whitish or yellow, are all terminal and solitary, and have often purplish bracts that are quite conspicuous. The tubular calyx is erect, and hairy in, the throat, and the two lipped corolla has two protruding anther-bearing stamens. A few flowers only open at a time, which leaves much of the rounded heads of the hairy calyces exposed.