Terminal pinky-mauve flower heads, rounded. Calyx-teeth pointed, slender. Additional whorls of flowers lower down stems. Stalked leaves opposite, hairy, oval. Coarse-toothed. Mint-scented. Stems often reddish. Height: To 90cm.
Permanently wet ground, can be terrestrial or more/less submerged. Found in and beside streams, ponds, marshes and other wet areas.
Similar: Whorled Mint, M. x verticillata