Description from Flora of China
Mentha cablin Blanco, Fl. Filip. 473. 1837; Pogostemon javanicus Backer ex Adelbert; P. patchouly Pelletier; P. patchouly var. suavis J. D. Hooker.
Herbs or subshrubs, perennial, aromatic. Stems erect, 30-100 cm tall, tomentose. Petiole 1-6 cm; leaf blade circular to broadly ovate, 2-10.5 × 1-8.5 cm, herbaceous, adaxially dark green, sparsely tomentose, abaxially tomentose, base cuneate-attenuate, margin irregularly incised, apex obtuse to acute; lateral veins ca. 5-paired. Spikes 4-6.5 × 1.5-1.8 cm, densely tomentose, terminal and axillary; verticillasters 10- to many flowered, basally somewhat lax; peduncle 0.5-2 cm; bracts and bracteoles linear-lanceolate, somewhat shorter than to as long as calyx, densely tomentose. Calyx tubular, 7-9 mm, tomentose outside, minutely tomentose inside; teeth subulate-lanceolate, ca. 1/3 as long as calyx tube. Corolla purple, ca. 1 cm, lobes villous outside. Stamens bearded. Fl. Apr.
Cultivated in China. Source of patchouly oil, an essential oil obtained from the leaves and used in soaps and perfumes. Employed in scenting carpets and shawls. It is also used medicinally.
Fujian, Guangdong, Guangxi, Hainan, Taiwan [India, Indonesia, Malaysia, Philippines, Sri Lanka]