Kentucky Bluegrass
Poa pratensis · Cool-season (C3), Perennial
Grass Family
Poaceae, Subfamily Pooideae, Tribe Poeae
Grass Category
Lawn/Turf Grass, Sports Turf, Golf Course Grass
Variety / Cultivar
Likely an elite cultivar (e.g., 'Midnight' or 'Mazama') or a standard turf-type blend
Hardiness Zones
USDA Zones 2-7; excellent cold tolerance; enters winter dormancy; struggles in the high heat of Zones 8-10.
About This Grass
A dense, high-quality turf with a hallmark dark green to blue-green color. It maintains a medium-fine texture and grows vertically until mowed. Seed heads are open panicles, though rarely seen in maintained lawns.
Blade Characteristics
Folded vernation; blade width 2-4mm (medium); distinct boat-shaped tip (keeled); prominent mid-rib on the upper surface; short, membranous ligule; auricles absent.
Root System
Moderately deep fibrous root system complemented by vigorous rhizomes; high thatch-forming tendency; moderate establishment speed from seed, excellent sod-forming ability.
Growing Information
Origin Region
Native to Europe, Northern Asia, and the mountains of Morocco and Algeria; naturalized throughout North America
Growth Habit
Rhizomatous (spreading via underground stems), forming a dense, self-repairing sod
Sunlight & Water Needs
Prefers full sun (minimum 6 hours); moderate to high watering needs; goes dormant during severe drought; prefers well-drained soil with pH 6.0-7.0.
Mowing & Maintenance
Ideal height 2.5-3.5 inches; weekly mowing; 2-4 lbs Nitrogen per 1000 sq ft annually; requires periodic dethatching and core aeration; high maintenance level.
Special Characteristics
High traffic/wear tolerance due to rhizomes; excellent recovery potential; susceptible to summer patch and necrotic ring spot; moderate salt tolerance.
Ecological Information
Introduced/Naturalized; provide cover for small mammals; excellent soil stabilizer for erosion control; commonly blended with Perennial Ryegrass or Fine Fescue.