Galangal

Sowing: Galangal is grown from rhizome setts bearing one or two buds, planted directly in spring once frost danger has passed and the soil has warmed, spaced about 30 cm apart in rows with 15–23 cm between plants and set 5–10 cm deep; it can also be raised from seed sown as soon as it ripens and kept around 20°C, or increased by dividing an established rootstock as new growth begins, with shoots appearing within about a week and two to three leaves forming within a month.

Growing: The plant thrives in warm, humid conditions with rainfall in the range of 2,000–3,700 mm and temperatures that do not fall below 15°C, in a well-drained, humus-rich soil with a pH of about 5.5–6.5, tolerating full sun but preferring partial shade and some drought. Frost scorches the foliage but rarely kills an established clump, which can spread vigorously once conditions suit it; outside the tropics it is grown as an evergreen perennial in warm zones or as an annual in cooler ones, and it adapts well to container culture indoors.

Rhizomes can be dug for most of the year, and gardeners can lift a few from the side of an established clump rather than harvesting the whole plant at once. Young, actively growing rhizomes have a paler, whitish skin and a more tender texture than older brown-skinned ones, and the root reaches its best harvest quality about three months after planting.

Culinary: The rhizome is the plant's primary product, used fresh or dried to flavour curries, soups, meats and fish across Cambodian, Indonesian, Lao, Malaysian, Thai and Vietnamese cooking, often paired with lemongrass. Its leaves and young shoots are eaten as a vegetable, its flowers and flower buds are eaten raw, steamed, pickled or mixed into chilli paste, and its red fruit is used as a substitute for cardamom; an essential oil extracted from the root also flavours liqueurs such as Chartreuse and Angostura and some soft drinks, and in Russia the rhizome flavours vinegar and the liqueur nastoika.

Ornamental: Beyond the kitchen, galangal is grown as an ornamental foliage plant for its glossy green leaves and fragrant pink, pinkish-white or yellowish-white flowers, which attract hummingbirds.

Medicinal: In Ayurvedic, traditional Thai and traditional Chinese medicine, galangal rhizome has historically been used against digestive complaints such as indigestion, colic and dysentery, as well as for skin conditions, respiratory ailments and after childbirth, and the rhizome was applied directly to the teeth as a folk remedy for toothache.

Other: The rhizome's essential oil has also been valued in Indian perfumery, and the plant has served as a source of yellow dye.

Galangal is native to South and Southeast Asia, with a range extending through China, Indo-China, India and Malaysia, and it has long been cultivated in tropical regions of southern Asia while still sometimes gathered from wild or semi-cultivated stands in old forest clearings. The rhizome reached Europe as a traded spice more than a thousand years ago, likely carried by Arab or Greek physicians, and had already been used as food and medicine by the ancient Romans before its documented arrival in Europe in the ninth century.