Acorus gramineus

What to Eat

Edible parts: Root - spice, Leaves - flavouring

The root can be eaten raw or cooked. It should be peeled, finely chopped, and soaked in several changes of water beforehand. It has a stronger and more pleasing taste than A. calamus and can also be used as a ginger substitute. Some caution is advised regarding toxicity.

Known Hazards

Where to Find It

It is a temperate plant. It grows well in shallow water and ponds. It grows in wetlands. It needs a sunny position. It can grow in well watered garden beds. In China it grows on moist rocky stream banks below 2,600 m above sea level. It suits hardiness zones 5-10. In Sichuan and Yunnan.

Asia, Australia, Cambodia, Canada, China, India, Indochina, Japan, Korea, Laos, Malaysia, Myanmar, North America, Northeastern India, Philippines, Russia, SE Asia, Siberia, Taiwan, Thailand, Tibet, Vietnam,

How to Identify

A shrub or small tree. It grows 5 m tall. There are prickles along the stem. The leaves are twice divided and there are 8-18 pairs of pinnae. There are up to 50 pairs of pinnules on each pinnae. The flowers are yellow. They are in large clusters at the ends of branches. The pods are flattened.

How to Grow

It can be grown from seed or by division of clumps. The seedlings need to be kept in moist soil.

Propagation: Seed is best sown in a cold frame as soon as it is ripe, with the pot stood in about 3cm of water. Pot up seedlings as soon as they are large enough to handle, keep them wet by standing pots in shallow water, and overwinter in a greenhouse or cold frame during the first year. Division in spring just before growth begins is very easy and can be carried out at any time during the growing season, planting directly into permanent positions.

Medicinal Uses

The root is antifungal, antibacterial, antiperiodic, antirheumatic, antispasmodic, aromatic, cardiac, carminative, diaphoretic, emmenagogue, febrifuge, sedative, stimulant, stomachic, tonic, and vermifuge. It is powdered and applied to bleeding gums. Internally it treats digestive problems — particularly gastralgia and diarrhoea — as well as cough, bronchial asthma, neurasthenia, depression, and epilepsy. Externally it is used for body parasites, dermatosis, and haemorrhoids. The root can be harvested at any time except when the plant is in flower. It contains an essential oil of asarone and asaryl aldehyde, plus the bitter glucoside acorin. Asarone increases the hypnotic effect of barbiturates and ethanol, lowers blood pressure, and is antibacterial against Staphylococcus aureus, streptococci, and mycobacterium. The whole plant is anodyne, antiperiodic, antispasmodic, digestive, diaphoretic, diuretic, expectorant, sedative, stimulant, stomachic, sudorific, tonic, and vermifuge.

Other Uses

The dried root repels insects and is probably insecticidal; in Vietnam it is used to kill lice, bugs, and fleas. An essential oil is obtained from the plant. It also makes a useful spreading ground cover.

Acorus gramineus, commonly known as Japanese sweet flag, Japanese rush, grassy-leaved sweet flag, and grass-leaf sweet flag, is a botanical species belonging to the genus Acorus, native to Japan, Korea, and eastern Asia. The plant usually grows in wetlands and shallow water. The genome of A. gramineus has been published by independent research groups in 2022 and 2023.

Notes

There are 2 Acorus species.

More from Acoraceae

Acorus calamus

Calamus, Sweet flag