Koraikizhangu is Cyperus rotundus, nutgrass — the purple nutsedge that ruins gardens and whose small, fragrant tubers Hindi shops call nagarmotha and Sanskrit lists call mustaka. It is a sedge, not a grass, and not vetiver. The weed and the perfume-and-list article are the same plant.
- Botanical name
- Cyperus rotundus L.
- Family
- Cyperaceae
- Tamil
- Koraikizhangu
- Hindi
- Nagarmotha
- Sanskrit
- Mustaka
- Parts used
- Tubers (culms are the weed)
- Habit
- Perennial sedge of waste ground; the article is the tuber
- Last updated
- 2026-10-30
How to recognise Koraikizhangu
Linnaeus published Cyperus rotundus. The family is Cyperaceae. It is a perennial with three-ranked leaves, a triangular stem, chestnut spikelets, and chains of dark tubers on rhizomes — the “nuts” that make it almost immortal in a bed.
The tuber is 1–2 cm, dark and irregular, with a woody-camphor smell when broken. Fresh garden tubers and dried nagarmotha in a tin should still share that smell.
Tamil koraikizhangu / korai, Hindi nagarmotha and Sanskrit mustaka are the names. English nutgrass and purple nutsedge are this species. Cyperus scariosus (a related perfume sedge) is a different article in some attar lists.
Vetiver is a true grass with a different, longer fragrant root. A packet that says only “fragrant root” has not named the family.
A Tamil vegetable bed and a Mediterranean waste lot can be the same unstoppable sedge.
Buy whole tubers and break one. Brown powder is a weak determination.
The above-ground weed is what gardeners spray. The underground chain is what lists want. They are one organism.
Pull a clump and you will see the beads of tubers like a dark necklace. That necklace is why the weed returns, and it is the tubers, washed and dried, that a mill wants — not the green tops.
Spikelets are chestnut, not the green of many lawn sedges. Flowering is a field mark; the tuber is still the trade object when the heads have gone.
Traditional use of Koraikizhangu
Ayurveda
Mustaka is a famous tuber in those lists, often in digestive and “fever” headings. Historical headings are not a modern claim.
Ayurvedic materia medica headings
Siddha and perfume
Korai is a Tamil tuber and a perfume material in some attars. Smell is not a diagnosis.
Tamil vernacular and Indian perfumery
Modern notes on Koraikizhangu
Weed-science papers on this plant outnumber careful human trials, which is the honest modern picture.
The practical modern issue is other Cyperus tubers in the same sack, and gardeners and vaithiyars wanting opposite things from one plant.
Koraikizhangu safety
A tuber in a traditional powder is the listed exposure. Essential oil is a different strength.
Do not eat unidentified sedge tubers from a sprayed lawn. Herbicide residue is a garden fact.
Pregnant people should not start mustaka from a shop poster.
Ecology and sourcing
It is one of the world’s worst weeds of cultivation and also a listed medicine. Conservation of the species is not in doubt. Honesty about sprayed ground versus a clean lot is.
Related plants
Questions about Koraikizhangu
Is nutgrass a grass?
No. It is a sedge, Cyperaceae. Grasses are Poaceae. The stem is triangular.
What is the Tamil name of Cyperus rotundus?
Koraikizhangu.
Sources
- Cyperus rotundus L. — Plants of the World Online, Kew (search) (accessed 2026)
- Wikidata item Q1391422 (Cyperus rotundus)
Educational page about a plant. It is not medical advice, not a diagnosis, and not an offer to sell. Traditional use is historical. If you need care, ask a licensed clinician. Questions: hello@meevamed.com.