Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
AI-generated identification · may be incorrect
Grass Category
Lawn/Turf Grass, Sports Turf
Hardiness Zones
USDA Zones 3-7 (thrives in northern climates and the northern transition zone), excellent cold tolerance, moderate heat tolerance.
Grass Family
Poaceae, subfamily Pooideae, tribe Poeae
Variety / Cultivar
'Midnight' or similar dark green elite cultivar
About This Grass
Forms a dense, high-quality, fine-to-medium textured turf with rich dark green to blue-green color. Reaches 18-24 inches if unmowed, maintained at 1.5-2.5 inches. Produces open, pyramidal panicle seed heads at maturity.
Blade Characteristics
Medium-fine width (2-4mm), V-shaped or folded in the bud (folded vernation), distinct boat-shaped tips, prominent parallel veins with a tram-line effect (double parallel lines near the midrib). Membranous ligule and absent auricles.
Root System
Moderately deep fibrous root system combined with extensive underground rhizomes. Forms a very tough, dense sod. Moderate establishment speed from seed, tends to build up thatch if heavily fertilized.
Growing Information
Origin Region
Europe, Northern Asia, and mountainous regions of North America; widely cultivated across cool temperate regions globally.
Growth Habit
Rhizomatous, spreading underground via aggressive creeping rhizomes to form a dense, uniform turf mat.
Sunlight & Water Needs
Requires full sun (minimum 6-8 hours daily), moderate to high water needs to maintain color during summer, enters summer dormancy (turns brown) during prolonged drought but recovers well. Prefers well-drained loamy soils with pH 6.0-7.0.
Mowing & Maintenance
Mow at 1.5 to 2.5 inches. Medium-high maintenance level. Requires 2-4 lbs N per 1000 sq ft annually. Regular aeration and occasional dethatching are recommended due to heavy rhizome production.
Special Characteristics
Outstanding wear tolerance and self-repairing capability via rhizomes. Moderate disease susceptibility (summer patch, dollar spot, leaf spot). Excellent winter color retention in milder cool regions.
Ecological Information
Introduced species in North America, provides turf and ground cover, stabilizes soil effectively against erosion, commonly blended with perennial ryegrass and fine fescues for home lawns and athletic fields.