Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3
Grass Family
Poaceae, subfamily Pooideae
Grass Category
Lawn/Turf Grass, Sports Turf, Golf Course Grass
Variety / Cultivar
Common or 'Midnight' type (typical characteristics visible)
Hardiness Zones
USDA Zones 3-7; high cold tolerance; enters summer dormancy during extreme heat; widely used in northern climates.
About This Grass
Dense, sod-forming turf with a medium to fine texture. Exhibits a rich dark-green to blue-green color. Mown height typically 1.5-3 inches. Features a panicle seed head if left unmowed.
Blade Characteristics
Blade width 2-4mm (medium); flat or slightly V-shaped; distinctly boat-shaped tip; dark green color; folded vernation; membranous ligule; no auricles.
Root System
Relatively shallow fibrous roots but extensive rhizomes; forms a thick thatch layer over time; moderate establishment speed; excellent wear recovery.
Growing Information
Origin Region
Europe, North Asia, and Northern Africa; well-adapted to temperate/cool climates worldwide
Growth Habit
Rhizomatous; forms a tight, dense sod via underground stems; medium rate of spread
Sunlight & Water Needs
Prefers Full Sun (6+ hours); moderate shade tolerance in specific cultivars; requires consistent moisture; poor drought tolerance (enters dormancy without water); prefers well-drained soil pH 6.0-7.0.
Mowing & Maintenance
Recommended height: 2.0-3.5 inches; high frequency (weekly); 3-5 lbs N per 1000 sq ft per year; high maintenance; requires periodic dethatching and aeration.
Special Characteristics
Excellent wear tolerance due to rhizomes; cold hardy; susceptible to summer patch and necrotic ring spot; high recuperative potential; provides a lush, high-quality aesthetic.
Ecological Information
Introduced/Naturalized in North America; provides forage for herbivores and nesting material for small birds; helps prevent soil erosion through dense sod formation; often blended with Perennial Ryegrass or Fine Fescues.