Mentha spicata L.
spearmint
Rhizomatous perennial with branched ± glandular-scaly stems ascending to c. 80 cm, glabrous, glabrate or grey-villous, often tinged red. Lvs sessile to very shortly petiolate, 2.5-9 × 0.7-2 cm, lanceolate to elliptic or ovate-elliptic to ovate or oblong, plane or rugose, either with scattered hairs on veins below, or densely hairy above and persistently grey-villous below; base cuneate to cordate; apex obtuse to shortly acuminate. Infl. of rather narrow, short or long, terminal spikes, the central one 4-12 cm long, usually sparsely hairy, sometimes grey-villous. Fls pedicellate. Calyx 1.5-2.2-(3.5) mm long, ± purple, sparsely dotted with glands; teeth lanceolate or linear-subulate, ciliate, acuminate, slightly < to = tube. Corolla 3-5 mm long, mauve or pinkish; lobes dotted with oil globules outside. Stamens included or exserted; anthers 0.35-0.4 mm long. Style long-exserted. Nutlets 0.5-0.7 mm long, broad-ovoid, minutely reticulate or granular, sometimes plant sterile.
Key
FL Jan-May.
M. spicata may be an allopolyploid derived from possibly M. longifolia and M. suaveolens and is only known as a cultivated plant or an escape from cultivation. Two subspp. occur in N.Z.
