Pycnanthemum Genus mountain mint Lamiaceae

Pycnanthemum is a genus of perennial, aromatic herbs (ours) with 4-sided, erect stems, colonial from rhizomes.

Leaves opposite, simple, aromatic.

Flowers white to pink, small, bilaterally symmetrical, tubular, 2-lipped, the upper lip entire or slightly notched, the lower lip 3-lobed, usually purple-dotted; stamens 4, usually longer than the petal lobes; ovary 4-lobed; flowers usually crowded in head-like clusters in leaf axils or ends of stems.

Fruit dry, of 4 nutlets cupped in the bottom of the persistent calyx.