10. Mentha crispata Schrader ex Willdenow, Enum. Pl. 608. 1809.
皱叶留香 zhou ye liu lan xiang
Herbs rhizomatous. Stems erect, 30-60 cm, purplish, glabrous. Leaves sessile or subsessile, ovate to ovate-lanceolate, 2-3 × 1.2-2 cm, papery, base rounded to shallow cordate, margin serrate, apex acute. Verticillasters in terminal spikes 2.5-3 × ca. 1 cm, continuous or ± interrupted at base; bracts linear-lanceolate, slightly longer than calyx. Pedicel ca. 1 mm. Calyx campanulate, ca. 1.5 mm, subglabrous, glandular, obscurely 5-veined; teeth triangular-lanceolate, ca. 0.1 mm, ciliate. Corolla purplish, ca. 3.5 mm, glabrous, tube ca. 2 mm; lobes subequal, apex emarginate. Ovary brown, glabrous. Nutlets brown, triquetrous, ovoid, ca. 0.7 mm, sparsely glandular.
Beijing Shi, Hangzhou Shi, Kunming Shi, Nanjing Shi, Shanghai Shi [Russia; Europe]
Cultivated in China. Source of German spearmint oil. Young shoots and leaves edible.
A form/cultivar of M. spicata Linnaeus.