Mentha canadensis.By Glen Mittelhauser. Copyright © Glen Mittelhauser. 2016.New England Wild Flower Society.gobotany.newenglandwild.org (Accessed 2/2016).

Mentha is a genus of perennial herbs (ours), colonial from rhizomes, aromatic, most with “minty” aroma; stems 4-sided. 

Leaves opposite, simple, most with puckered by impressed veins; margins toothed. 

Mentha spicata.fruit.Manel Casanova.menudanatura.com.creative commons.org (Accessed 2/2016).

Flowers white to blue or lavender, small, tubular, 4-parted and nearly radially symmetrical by fusion of 2 upper lobes, this lobe wider and usually notched at tip; calyx tubular 4-parted, lobes pointed; stamens 4, longer than corolla; ovary superior, deeply 4-parted; inflorescence of axillary clusters or terminal spikes flowers in small, dense cushions at nodes subtended by leafy bracts; pollinated by bees (Lovell 1918). 

Fruit dry, of 4 nutlets.