Tubers are the only plant part to overwinter. The stems are erect, 15-76 cm tall, waxy, triangular, and unbranched.
Triangular stems are characteristic of the sedge family.
The leaves are grass-like, long and narrow, shiny, hairless, with closed sheaths. The flowers are brown and occur as sessile spikes in an umbel. The seeds are 3-sided achenes that are white to brown in colour. Yellow nutsedge's prolific growth results in a 3000-fold increase in reproductive potential during the course of one growing season. This weed thrives in moist soil, growing along river banks and is spread by flood water and cultivation.