Acorus calamus

Family : Acoraceae
Common names
: sweet-flag ( Eng. ); makkalmoes (Afr.); ikalamuzi (Zulu)


Acorus calamus is a reed-like, aquatic plant with a pungent smell that has been used medicinally since biblical times. It has many traditional uses all over the world and is well known as a digestive and carminative.

A. calamus is an aquatic perennial herb growing from long, creeping rhizomes which are aromatic. The aromatic leaves are shaped like swords, are more than 15 mm wide and have a distinctive midrib and reddish colour at the base. The small flowers are grouped together in a small, oblong spike.

Distribution and habitat
This plant originated from Asia but has been cultivated in South Africa since early colonial times along streambanks and in wetlands. It is now distributed all over the country and has become naturalized.

Uses and cultural aspects
The aromatic, bitter rhizomes are used in the treatment of indigestion, flatulence and diarrhoea. It is also used to stimulate appetite. Its traditional uses are mainly as a digestive and carminative and sometimes as an emetic, anti-spasmodic and anthelmintic. It also appears to relieve chronic dysentery and asthma, and to have a strengthening effect on the nervous system. It has been applied in Chinese medicine.

The essential oil extracted from the rhizomes is used in perfumery and the powdered rootstock is used as an insecticide against fleas and other insects. It is also believed that cobras dislike the smell of this plant due to the narcotic effect that it produces. The rootstock is also fermented with sugar, corn and water to make traditional beer.

This plant was found in Tutankhamen's tomb in Egypt and is mentioned in the Old Testament in Exodus 30. The use of Acorus in digestive medicines has been discontinued in most countries due to possible harmful effects.

Growing Acorus calamus

It is easily propagated from root cuttings and from seed. It grows well in wet environments such as streambanks and wetlands.

References and further reading

  • Bruneton, J. 1999. Pharmacognosy, photochemistry, medicinal plants, edn 2. Lavoisier, Paris?.
  • Van Wyk, B-E., Van Oudtshoorn, B. & Gericke, N. 2000. Medicinal plants of South Africa. Briza Publications, Pretoria.
  • Van Wyk, B-E. & Wink, M. 2004. Medicinal plants of the World. Briza Publications, Pretoria.
  • Watt, J-M. & Brandwijk, M.G.B. 1962. Medicinal plants of southern and eastern Africa. Livingstone, London .


If you enjoyed this webpage, please record your vote.

Excellent - I learnt a lot
Good - I learnt something new

Joseph Khangela Baloyi & Linette Ferreira
Pretoria National Botanical Garden
March 2005


This page forms part of the South African National Biodiversity Institute's plant information website