Lamiaceae, the Mint family, consists of about 200 genera and 3,200 species worldwide, mostly perennial or annual herbs and shrubs (rarely trees). They are usually easily recognizable by having square stems and opposite or whorled leaves. Many of the species are aromatic, making them further recognizable. Lamiaceae (formerly Labiatae) receives a lot of interest, as many members of the family possess high economic and other useful qualities. These plants characteristically bear essential oils in the form of their crushed foliage. Despite their identifiable qualities, they are a family of great diversity and variety. The flowers of Lamiaceae are bilaterally symmetrical, have 5 united sepals, 5 united petals, usually arranged so as to form an upper and often lower lip, stamens are 2 to 4. All these parts attached at the base of the ovary. The flowers grow in long clusters, heads, or interrupted whorls on the stem. The leaves vary from simple (typical in our area) to pinnately or palmately dissected or compound, are either opposite or whorled (3 – 10 per whorl) and are usually toothed. They are almost always aromatic (very rarely lacking an odor). The leaves are either one–veined, pinnately veined, or palmately veined, and either heart shaped (or close to it) or rounded at the base. As explained above, the stems of this family have a unique square (4-sided) shape about them. The fruit has 4 lobes, each forming a hard, single-seeded nutlet, rarely a stone.
Guide to Identify Presented Species of the Mint Family
FLOWERS WHITE, IN DENSE TERMINAL CLUSTERS
Mentha spicata Spear Mint Stems single, erect, 30-100 cm tall. Ditches and streambanks.
Flowers whitish, 2-4 mm long, tubular, 4-lobed, clustered in dense, tall spikes.
Leaves opposite, broadly lance-shaped, sharp-toothed, pointed, 2-7 cm long.
Nepeta cataria Catnip Stems branched, 30-100 cm tall, short-gray-hairy. Meadows, roadsides.
Flowers white with small purple dots, 10-15 mm long, in dense, tall clusters.
Leaves opposite, coarsely toothed, stalked, heart-shaped, 2.5-7 cm long.
FLOWERS PINK OR PURPLE, IN TERMINAL CLUSTERS
Monarda fistulosa Wild Bergamot Stems single, 30-70 cm tall, with minty odor. Moderately dry, open sites.
Flowers pink-purple, tubular, c. 3 cm long, in dense clusters above leafy bracts.
Leaves opposite, broadly lanceolate, sharp-toothed, 2.5-8 cm long.
Prunella vulgaris Self-heal Soft-hairy low plant, 5-30 cm tall. Moist, open to shaded sites, plains-montane.
Flowers purple, tubular, 1-2 cm long, with a hooded upper lip, in short spikes.
Leaves opposite, few pairs, lance- to egg-shaped, entire, stalked, 2-9 cm long.
FLOWERS SMALL, IN SEVERAL CLUSTERS FROM UPPER LEAF AXILS
Marrubium vulgare Horehound Plant 30-100 cm tall. Casual weed along roadsides and disturbed habitats.
Flowers whitish, about 6 mm long, in dense, round clusters from upper leaf axils.
Leaves opposite, thick, rounded, toothed and coarsely wrinkled, 20-55 mm long.
Mentha Mint Aromatic, hairless or long-hairy plants, 20-80 cm tall. Moist to wet sites.
Flowers pink-white, 4-7 mm long, 4-lobed, in dense heads from upper leaf axils.
Leaves opposite, 2-8 cm long, lance-shaped, sharp-toothed, mostly stalkless.
FLOWERS FEWER, FROM UPPER LEAF AXILS
Lamium amplexicaule Henbit Dead-nettle Slender annual, 5-15 cm tall, with creeping base. Weed, fields, disturbed areas.
Flowers pink-purple, 12-18 mm long, hooded, 2-lipped, from upper leaf axils.
Leaves opposite, rounded, coarsely round-toothed, about 1.5 cm long.
Alphabetical listing with links to presented species of the Mint family: