Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, Subfamily Pooideae, Tribe Poeae
Grass Category
Lawn/Turf Grass, Sports Turf, Golf Course Grass
Variety / Cultivar
Common or Elite type (e.g., 'Midnight' or 'Baron' typical phenotypes)
Hardiness Zones
USDA Hardiness Zones 3-7; excellent cold tolerance; poor heat tolerance in the Deep South; goes dormant in winter/summer extremes.
About This Grass
A dense, high-quality turf with a low-growing habit. Features a distinctive dark green to blue-green color. Seed heads are open, pyramid-shaped panicles, though rarely seen in maintained lawns.
Blade Characteristics
Fine to medium width (2-4mm); V-shaped or flat; distinctive boat-shaped (keeled) tip; smooth texture with a prominent midrib; folded vernation; short membranous ligule; auricles absent.
Root System
Moderately shallow fibrous root system supplemented by strong rhizomes. High thatch-forming tendency; slow to medium establishment from seed but excellent self-repairing sod.
Growing Information
Origin Region
Native to Europe, Northern Asia, and the mountains of Morocco and Algeria; highly adapted to temperate climates
Growth Habit
Rhizomatous (spreading via underground stems), forming a dense, uniform sod with a moderate to slow spread rate
Sunlight & Water Needs
Full sun preferred (requires 6-8 hours); moderate to high water needs; enters dormancy during severe drought; prefers well-drained fertile soil with pH 6.0-7.5.
Mowing & Maintenance
Ideal height 2.0-3.5 inches; weekly mowing; high fertilization (2-4 lbs N per 1000 sq ft/year); requires periodic dethatching and aeration; high maintenance level.
Special Characteristics
Excellent wear tolerance and recovery due to rhizomes; susceptible to necrotic ring spot and summer patch; low shade tolerance; high aesthetic value.
Ecological Information
Introduced and naturalized in North America; provides bird nesting cover in unmowed areas; good soil stabilization; often blended with Perennial Ryegrass or Fine Fescue.