Purple Nutsedge
Cyperus rotundus · Warm-season, Perennial, C4 sedge
Grass Family
Cyperaceae
Grass Category
Invasive/Weed Grass (Sedge)
Variety / Cultivar
Wild type (not a cultivated turf variety)
Hardiness Zones
USDA Hardiness Zones 7 through 11. Sensitive to freezing temperatures which kill top growth, though tubers survive underground.
About This Grass
An aggressive, fast-growing sedge with distinct triangular stems and glossy, dark green leaves. Unmowed height reaches 10 to 40 inches. It often stands out in a dormant turf due to its rapid vertical growth and vibrant green color.
Blade Characteristics
Medium-width leaves (3-8 mm) originating primarily from the base with a V-shape in cross-section. Pointed tips, glossy dark green color, rolled vernation, prominent midvein, smooth texture, and no ligules or auricles.
Root System
Extensive, deep underground network consisting of fibrous roots, rhizomes, and small, nut-like tubers (nutlets) connected in chains. High thatch tendency, very rapid establishment, difficult to eradicate due to tubers.
Growing Information
Origin Region
Native to Africa, southern and central Europe, and southern Asia; now a global weed found in tropical and subtropical regions.
Growth Habit
Aggressive rhizomatous and tuber-bearing perennial forming dense patches via underground tubers and stolons.
Sunlight & Water Needs
Requires full sun, thrives in moist to wet soils but tolerates drought once established. Highly adaptable, prefers poorly drained soils and warm temperatures.
Mowing & Maintenance
Hard to control by mowing alone due to rapid growth rates and low-growing crowns. Responds to regular lawn mowing by flattening out. High maintenance to eradicate.
Special Characteristics
Extremely high weed aggressiveness, very difficult to control with standard selective broadleaf herbicides (requires sedge-specific treatments like halosulfuron), tolerates compacted soils, low wear tolerance compared to dense turf.
Ecological Information
Considered one of the world's worst agricultural weeds. Provides little positive value in cultivated landscapes, outcompetes native vegetation and turfgrasses rapidly.