Mentha spicata is a perennial herb from rhizomes, stems 0.3-1 m tall, square, mostly hairless, strong minty odor, often reddish towards base; larger plants usually branched below inflorescence.
Leaves opposite, stalk 0-0.3 cm long, blade 3-7 cm long, 1-2.5 cm wide, narrowly egg-shaped to lance-shaped, surface puckered by deeply impressed veins, tip pointed, base rounded, margin toothed.
Flowers blue-purplish, corolla 0.2-0.4 cm long, petal lobes 4, almost regular; calyx 0.1-0.3 cm long, lobes fringed with hairs, narrow, purplish; anthers and stigma longer than petal tube; Inflorescence of terminal spikes 3-12 cm long, 0.5-1 cm wide, flowers in dense, mostly closely spaced whorls at each node, subtended by linear bracts; blooms July-Oct.
Fruit dry, of 4 nutlets.
Wetland status: FACW+.
Frequency in NYC: Very infrequent.
Habitat: Open wet areas, wet pockets in fill, disturbed sites.
Notes: A traditional medicinal and culinary herb. More invasive than M.x piperita (Fern 2004).