L., Sp. Pl. 576 (1753) subsp. spicata.
Synonymy: M. viridis (L.)L., Sp. Pl. edn 2:804 (1763); M. spicata L. var. viridis L., Sp. Pl. 576 (1753).
Common name: Spearmint.
Perennial herbs with a rhizome usually underground and frequently rooting at the nodes, producing erect quadrangular stems to 1 m high, tinged purplish, more or less branched, glabrous or with scattered simple hairs; leaves sessile, lanceolate, ovate or ovate-oblong, 2-9 x 0.13.5 cm, cordate, crenate, serrate, with 8-10 pairs of secondary veins, glabrous to slightly hairy and with sessile glands on the undersurface.
Inflorescence a thyrse with a distinct peduncle and often branched below, with sessile cymose part-inflorescences with many pedicelled flowers in dense clusters each subtended by linear to variously lobed slender bracts and internodes between fertile nodes rarely elongated and slightly separating some lower flower clusters; sepals regularly connate to about half their length, 10-veined, 1-2.5 mm long, with pointed lobes, glabrous to hairy and with sessile glands on the outside, glabrous inside; corolla lilac, pink or white, vaguely 2-lipped with the posterior lip scarcely 2-lobed to emarginate or truncate, with the anterior lip with 2 subequal lateral lobes and an anterior one, with few hairs and sessile glands on the outside, glabrous inside; stamens inserted just below the throat of the corolla tube, with filaments glabrous; anthers 2-celled, more or less exserted; ovary on a thick disk, 4-lobed, with a slender style inserted near the base, with a shortly 2-fid stigma.
Mericarps broadly obovoid to almost spherical, c. 1.5 mm long, not keeled, with the attachment scar including 2 basal concavities on either side of the lowest point, smooth to minutely granulate.
||Flowering branch of form B, leaf of form A.
Image source: fig. 554I,J in Jessop J.P. & Toelken H.R. (Ed.) 1986. Flora of South Australia (4th edn).|
Apart from the wild form of this species a very distinct cultivated form with broader leaves is more commonly grown in gardens. These 2 forms may be construed as 2 distinct species but Harley (1972) Fl. Europaea 3:186 and previous workers have considered them as extreme forms of a widely cultivated species M. spicata. Both forms have been recorded established in areas not under cultivation.
Flowering time: No flowering time is available
SA Distribution Map based
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