Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, subfamily Pooideae, tribe Poeae
Grass Category
Lawn/Turf Grass, Sports Turf
Variety / Cultivar
Standard turf-type blends (e.g., 'Midnight', 'America')
Hardiness Zones
USDA Hardiness Zones 3-7. Excellent cold tolerance, goes dormant and turns brown under severe summer heat and drought.
About This Grass
Forms a dense, fine-to-medium textured turf with a rich dark green to blue-green color. Reaches up to 18-24 inches if left unmowed, but maintained at 2-3 inches. Features boat-shaped leaf tips.
Blade Characteristics
Medium width (2-4mm), folded in the bud (vernation), prominent parallel veins with two clear translucent lines on either side of the midrib, boat-shaped tips, short membranous ligule, and absent auricles.
Root System
Moderately deep fibrous root system with aggressive underground rhizomes. Forms a very tough, dense sod. Medium establishment rate from seed.
Growing Information
Origin Region
Europe and northern Asia; widely naturalized and cultivated across North America
Growth Habit
Aggressively rhizomatous, forming a dense, uniform turf mat
Sunlight & Water Needs
Requires full sun (minimum 6 hours daily), moderate to high watering needs, moderate drought tolerance with summer dormancy capability, and prefers well-drained fertile soils with a pH of 6.0-7.0.
Mowing & Maintenance
Mow at 2.0 to 3.0 inches. High maintenance level requiring regular fertilization (3-4 lbs N per 1000 sq ft annually), frequent irrigation, and periodic dethatching and core aeration.
Special Characteristics
Excellent wear tolerance and self-repairing capabilities due to rhizomes. Good winter color retention in cooler zones. Moderate shade tolerance.
Ecological Information
Introduced species in North America. Used extensively in lawn blends with ryegrass and fescue. Provides good soil stabilization and erosion control.