Cyperus longifolius, commonly known as Longleaf Sedge, is a perennial herbaceous plant belonging to the sedge family. It is native to wetlands and marshy areas in the islands of Madagascar, Mauritius, and Réunion, where it thrives in moist, nutrient-rich soils. This sedge typically forms dense clumps and can reach heights of up to 3 feet (1 meter), with long, grass-like leaves that may exceed the height of the stems. The inflorescences are umbrella-like clusters of brownish spikelets that appear in the summer months, though they are not particularly showy.

Longleaf Sedge is valued for its ability to stabilize soil and its use in water purification in its native habitat. In cultivation, it can be used in rain gardens, wetland restoration projects, and as an ornamental grass in water features or bog gardens. It requires consistent moisture and can tolerate standing water, making it suitable for pond edges and other wet areas. It prefers full sun to part shade and can adapt to a variety of soil types, provided they are kept wet. While it has ornamental qualities, caution is advised when planting Cyperus longifolius outside its native range due to its potential invasiveness. It can spread rapidly and outcompete native vegetation, so it is important to monitor its growth and control its spread to prevent ecological disruption.CC BY-SA 4.0