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
Common or elite blend (such as 'Midnight' or 'Baron')
Hardiness Zones
USDA Hardiness Zones 3 to 7, thriving best in northern cooler climates with cold winters and moderate summers.
About This Grass
Forms a dense, fine-to-medium textured lawn with a vibrant medium to dark green color. Reaches up to 18-24 inches if left unmowed, but maintained at 2-3 inches. Features pyramidal panicle seed heads at maturity.
Blade Characteristics
Blades are medium-fine (2-3 mm wide), flat or folded with distinct parallel veins and characteristic boat-shaped tips. Vernation is folded in the bud with a short, membranous ligule and absent auricles.
Root System
Moderate depth fibrous root system with extensive aggressive rhizomes. Can develop a noticeable thatch layer under high fertility, establishes moderately slowly from seed, but recovers exceptionally well from wear via rhizomes.
Growing Information
Origin Region
Europe, northern Asia, and parts of the mountains of North America; widely naturalized and cultivated across the northern United States and Canada.
Growth Habit
Aggressively rhizomatous, forming a dense, uniform turf mat and sod.
Sunlight & Water Needs
Requires full sun (minimum 6-8 hours daily) with moderate to high water needs. Good cold-weather dormancy survival, moderate drought tolerance by going dormant during extreme dry spells.
Mowing & Maintenance
Ideal mowing height is 2.0 to 3.0 inches. Medium to high maintenance level, requiring regular fertilization (2-4 lbs N per 1000 sq ft annually), periodic aeration, and dethatching.
Special Characteristics
Excellent wear and traffic tolerance due to aggressive rhizomatous spread, good cold hardiness, moderate disease susceptibility (leaf spot, summer patch), poor shade tolerance compared to fescues.
Ecological Information
Introduced species in North America; provides standard urban wildlife and lawn habitat, excellent for erosion control on slopes due to dense sod formation, commonly blended with Perennial Ryegrass and Fine Fescue.