Mentha ×rotundifolia

Erect, rhizomatous herb to c. 60 cm, rooting at lower nodes; branches villous, often reddish. Leaves broadly elliptic or broadly ovate, 20–60 mm long, 15–45 mm wide, upper surface with moderately dense septate and sometimes arachnoid hairs, lower surface grey-villous with at least some hairs (usually along veins) branched, veins usually strongly impressed above, apex rounded, base cordate or truncate, margin crenate to serrate; sessile. Inflorescence terminal, 4–10 cm long, often branched at or near base; flowers in dense, many-flowered clusters, lower internode(s) usually apparent; pedicels shorter than calyx. Calyx 1.5–2.5 mm long, 10-veined, lobes half to as long as tube or slightly shorter, villous; corolla pink to pale lilac, exceeding calyx by 1–1.5 mm, lobes c. 1 mm long, the posterior one entire or barely emarginate; anthers not or barely exserted. Flowers ?Feb.–Apr.