Pogostemon cablin Benth.

Erect, aromatic, branched herb, 0.5-1 m. Stem and branches tomentose. Leaves thin-or thick-membranaceous, narrowly ovate or ovate, 5-10 (-14) by 3.5-6.5(-10) cm, with short appressed hairs; apex acute, base cuneate-rounded to truncate, sometimes oblique, always entire; margin elsewhere incisely dentate or crenate or partly double-serrate; petiole l-3.5(-6.5) cm, tomentose. Spicate racemes 3 or many forming a terminal panicle, 15-30(-40) cm long; verticillasters slightly apart below, closely approximate above, grey pubescent, with dense cincinni of seriately imbricating, lanceolate, acute bracts, sometimes ± secund. Calyx tubular, 4-5 mm long, in fruit 5-6 mm, narrowed at both ends, pubescent, without bristles, equally 5-toothed. Corolla white, lavender blue, or violet, 6-7 mm long. Filaments soft hairy. Style 2-branched at the apex. Nutlets ellipsoid, 0.6-1 mm long, 0.5-0.6 mm broad, sub-triquetrous, smooth, black.

A tropical plant. It needs to grow in the tropics or subtropics. In Fiji it grows from sea level to 400 m altitude. In Nepal it grows between 100-1,000 m above sea level. It cannot tolerate frost. It can grow in soils with a pH between 5.5-8.0. It suits hardiness zone 10.

Uses. The leaves are widely extracted for the well-known patchouli oil of commerce, not to be confused with that extracted from Microtoena insuavis (Khasya patchouli), from Pogostemon heyneanus (Indian patchouli), and that of Pogoste-mon hortensis. Patchouli oil is used in perfumes and cosmetics. According to QUISUMBING (l.c. 830) the crushed leaves are often used for hair-washing in the Philippines. Furthermore, the leaves and innovations are employed as an insecticide against cockroaches, moths, etc., and as a repellent for leeches, and they are also added to baths for their presumed antirheumatic quality. An infusion of fresh leaves is taken internally to allay painful menstruation.

Plants can be grown from seeds but often plants don't form seeds. It is best grown from stem cuttings. Stem cuttings 10-15 cm long with 3-4 nodes are best. These are best put in a nursery and rooting hormone used. It can be transplanted after 3-4 months. A spacing of 60-90 cm is suitable.