Lemongrass (Cymbopogon citratus) is a dense, clump-forming grass that is found in tropical and subtropical grassland throughout southeast Asia. It can reach a height of around 2 metres with leaves that are white on the top and green on the underside. Lemongrass flowers are red to reddish-brown in colour.
Cymbopogon citratus is abundant in the Philippines and Indonesia, where it is known as tanglad or sereh. Lemongrass leaves are too tough for the body to digest, so they either need to be removed before eating or chopped vary finely. Both the stems and leaves feature in Asian, African and Latin American cuisine in teas, soups and curries. It has a subtle citrus flavour that complements poultry, fish, beef and seafood dishes in particular.
Lemongrass is sometimes used in folk medicine, particularly in India and Brazil. The plant is believed to have a range of medicinal applications with its supposed hypnotic, anticonvulsant, antibacterial and antifungal properties. Though many of these believed effects have not been supported scientifically, some studies have shown that it does have antioxidant, anti-inflammatory and antifungal properties.
Citronellol, one of the essential oils that can be made from the plant, has antihypertensive properties. In other words it can lower blood pressure by relaxing the muscles of blood vessels, which results in increased blood flow and decreased tension. Hydrosol, a by-product of the distillation process used to extract the essential oils from lemongrass, is used in skin care products as a weaker alternative to the oils. In some individuals Cymbopogon citratus oil can cause contact dermatitis, whereby the skin is irritated and becomes swollen and sore.
The oil extracted from Cymbopogon citratus is a popular insect repellent. It is particularly favoured for use against the stable flies that bite domesticated animals. Though it repels most insects, beekeepers are very fond of lemongrass oil as it can be used to attract honey bees when they swarm. In addition to these, lemongrass oil is also used in perfumes and is a popular houseplant as it gives a room a ‘fresh’ fragrance. The plant is also grown on embankments in South and Southeast Asia as a means of soil conservation.