Patchouli (Pogostemon cablin) is a species of plant from the family Lamiaceae, commonly called the “mint” or “deadnettle” family. The plant grows as a bushy herb, with erect stems reaching around 75 centimetres (2.5 ft) in height and bearing small, pale pink-white flowers. It is native to tropical regions of Asia, and is now extensively cultivated in China, Indonesia, Cambodia, Myanmar, India, Maldives, Malaysia, Mauritius, Seychelles, Madagascar, Taiwan, the Philippines, Thailand, Vietnam, South America and the Caribbean.
Extraction of patchouli’s essential oil is by steam distillation of the dried leaves, requiring rupture of its cell walls by steam scalding, light fermentation, or drying. The main chemical component of patchouli oil is patchoulol, a sesquiterpene alcohol.
Leaves may be harvested several times a year and, when dried, may be exported for distillation. Some sources claim a highest quality oil is usually produced from fresh leaves distilled close to where they are harvested; others that boiling the dried leaves and fermenting them for a period of time is best.