Local name: Bojho

Scientific name: Acorus calamus

Family: Araceae

Habitat and Ecology: On the edges of lakes, stream, and watery area.


A rhizomatous herb growing on marshy places. Leaves are bright green, 15 - 25 cm long and 0.2 - 0.5 cm broad, uniform with distinct midrib. Flowers small, yellow green arranged in cylindrical spandex.

Known since biblical times, the aromatic rhizome (underground stem) of Acorus calamus L. is commonly referred to as calamus or sweet flag, Bhojo in Nepali. Calamus has been taken over the centuries as a remedy for various sorts of digestive upsets and colic, especially in children. Calamus is a perennial herb.

It is commonly found in moist habitats such as the banks of ponds or streams and in swamps throughout Nepal.

Distribution in Nepal: 500 - 2300 m, east to west

The essential oil is obtained by steam distillation of the dried comminuted rhizome of calamus.

Specification of Calamus
1. Organoleptic Properties
Appearance Slightly viscous liquid
Color Yellow to yellowish brown
Aroma Warm woody-spicy
2. Physico-chemical Properties
Specific gravity 1.0695 to 1.0795 at 23°C.
Optical rotation (-) 0.2º to (-) 0.5º at 23º C
Refractive index 1.5335 t0 1.5589 at 23°C.
Acid number 0.6 to 2.5
Ester number 2 to 12
Ester number after acetylation 8.5 to 12
Solubility Soluble in 0.4 to 1.5 volume of 80% alcohol
3. Chemical constituent -
4. Uses:
  1. In perfumes of the woody oriental type: In spice blends and flavors for alcoholic beverages.
  2. Aromatherapetic uses: Calamus causes increased dilation of spleenic vessels, an important factor in regulating blood pressure.

Essential Oil