Perennial Ryegrass
Lolium perenne · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, Pooideae, Tribe Poeae
Grass Category
Lawn/Turf, Pasture, Sports Turf, Erosion Control
Variety / Cultivar
Common Perennial Ryegrass (Diploid/Tetraploid types)
Hardiness Zones
USDA Zones 5-7; excellent cold tolerance but poor heat and drought tolerance compared to tall fescue.
About This Grass
A fine-to-medium textured grass known for its dark green luster and narrow growth habit. Characterized by a distinctive flat spike seed head where spikelets are attached edgewise to the rachis.
Blade Characteristics
Width: 2-4mm; Shape: Flat; Tip: Pointed; Color: Dark green with a prominent glossy/shiny underside; Vernation: Folded in the bud; Ligule: Short, membranous; Auricles: Small, soft, claws-like.
Root System
Fibrous root system; moderate depth; fast establishment; low thatch tendency; limited drought recovery due to lack of spreading structures.
Growing Information
Origin Region
Europe and North Africa; now naturalized worldwide in temperate climates
Growth Habit
Bunch-type (clump-forming); lacks rhizomes and stolons
Sunlight & Water Needs
Full sun preferred; moderate shade tolerance; high water requirements; prefers fertile, well-drained soils with pH 6.0-7.0.
Mowing & Maintenance
Mowing height: 1.5-2.5 inches; Frequency: High during peak growth; Fertilization: 2-4 lbs N/1000 sq ft/year; Maintenance: Medium to High.
Special Characteristics
Highest wear tolerance of cool-season grasses; very rapid germination (5-7 days); salt tolerant; susceptible to Red Thread and Gray Leaf Spot.
Ecological Information
Introduced species; high forage value for livestock; provides cover for small mammals; often used in mixtures with Kentucky Bluegrass for soil stabilization.