Patchouli (Pogostemon cablin (Blanco) Benth; also patchouly or pachouli) is a species of plant from the genus Pogostemon. It is a bushy herb of the mint family, with erect stems, reaching two or three feet (about 0.75 metre) in height and bearing small, pale pink-white flowers. The plant is native to tropical regions of Asia, and is now extensively cultivated in China, Indonesia, India, Malaysia, Mauritius, Taiwan, the Philippines, Thailand, and Vietnam, as well as West Africa.
The heavy and strong scent of patchouli has been used for centuries in perfumes, and more recently in incense, insect repellents, and alternative medicines. The word derives from the Tamil patchai (Tamil: பச்சை) (green), ellai (Tamil: இலை) (leaf). In Assamese it is known as xukloti.
Patchouli grows well in warm to tropical climates. It thrives in hot weather, but not direct sunlight. If the plant withers due to lack of water, it will recover well and quickly after rain, or watering. The seed-producing flowers are very fragrant and bloom in late fall. The tiny seeds may be harvested for planting, but they are very delicate and easily crushed. Cuttings from the mother plant can also be rooted in water to produce additional plants.
Extraction of essential oil 
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 baling the dried leaves and fermenting them for a period of time is best.
Aroma profile 
Patchouli is used widely in modern perfumery and modern scented industrial products such as paper towels, laundry detergents, and air fresheners. Two important components of its essential oil are patchoulol and norpatchoulenol.
Insect repellent 
One study suggests patchouli oil may serve as an all-purpose insect repellent. More specifically, the patchouli plant is claimed to be a potent repellent against the Formosan subterranean termite.
During the 18th and 19th century, silk traders from China traveling to the Middle East packed their silk cloth with dried patchouli leaves to prevent moths from laying their eggs on the cloth. It has also been proven to effectively prevent female moths from adhering to males, and vice versa. Many historians speculate that this association with opulent Eastern goods is why patchouli was considered by Europeans of that era to be a luxurious scent. It is said that patchouli was used in the linen chests of Queen Victoria in this way.
Patchouli is an important ingredient in East Asian incense. Both patchouli oil and incense underwent a surge in popularity in the 1960s and 1970s in the US and Europe, mainly due to the hippie movement of those decades.
Notes and references 
- "Patchouli". Online Etymology Dictionary. Retrieved 10 December 2011.
- Grieve, Maude(1995) A Modern Herbal . 2007
- Leung A, Foster S Encyclopedia of common natural ingredients used in food, drugs and cosmetics John Wiley and Sons 1996
- Hasegawa, Yoshihiro et al.; Tajima, Katsuhiko; Toi, Nao; Sugimura, Yukio (1992). "An additional constituent occurring in the oil from a patchouli cultivar". Flavour and Fragrance Journal 7 (6): 333–335. doi:10.1002/ffj.2730070608.
- Weyerstahl, Peter et al.; Gansau, Christian; Marschall, Helga (1993). "Structure-odour correlation. Part XVIII. Partial structures of patchoulol with bicyclo[2.2.2]octane skeleton". Flavour and Fragrance Journal 8 (6): 297–306. doi:10.1002/ffj.2730080603.
- Hybertson, Brooks M. (2007). "Solubility of the sesquiterpene alcohol patchoulol in supercritical carbon dioxide". Journal of Chemical Engineering Data 52 (1): 235–238. doi:10.1021/je060358w. PMC 2677825. PMID 19424449.
- Nikiforov, Alexej et. al; Jirovetz, Leopold; Buchbauer, Gerhard; Raverdino, Vittorio (1988). "GC-FTIR and GC-MS in odour analysis of essential oils". Microchimica Acta 95 (1 – 6): 193–198. doi:10.1007/BF01349751.
- Ballentine, Sandra (5 November 2010). "Vain Glorious | Sex in a Bottle". Tmagazine.blogs.nytimes.com. Retrieved 10 December 2011.
- Trongtokit, Yuwadee; Rongsriyam, Yupha; Komalamisra, Narumon; Apiwathnasorn, Chamnarn (2005). "Comparative repellency of 38 essential oils against mosquito bites". Phytotherapy Research 19 (4): 303–309. doi:10.1002/ptr.1637.
- Foster, Steven; Johnson, Rebecca L. (2006). Desk Reference to Nature's Medicine. Washington, D.C.: National Geographic Society. p. 282. ISBN 978-0-7922-3666-5.