Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3
Grass Family
Poaceae, Subfamily Pooideae, Tribe Poeae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common-type (likely a multi-cultivar blend in residential turf)
Hardiness Zones
USDA Zones 2-7; excellent cold tolerance; poor heat tolerance; goes dormant in winter and extreme summer heat.
About This Grass
A medium-textured, cool-season grass with a distinct dark green to blue-green color. It forms a lush, carpet-like turf and is known for its horizontal spreading capability via rhizomes. When unmowed, it produces panicle-type seed heads that are pyramid-shaped.
Blade Characteristics
Narrow to medium (2-4mm) width; flat or slightly V-shaped; distinctly boat-shaped tip (keeled); dark green color; folded vernation in the bud; short membranous ligule; no auricles.
Root System
Relatively shallow fibrous root system with extensive horizontal rhizomes; forms a tight sod but has low drought tolerance compared to fescue; moderate establishment speed.
Growing Information
Origin Region
Europe, Northern Asia, and North Africa; widely naturalized in North America
Growth Habit
Rhizomatous (spreading via underground stems) that forms a dense, uniform sod
Sunlight & Water Needs
Full sun preferred (6+ hours); poor shade tolerance; high water requirements; enters summer dormancy during extended drought to survive; prefers well-drained soil with pH 6.0-7.0.
Mowing & Maintenance
1.5 to 3.0 inches height; weekly mowing; 2-4 lbs Nitrogen per 1000 sq ft per year; high maintenance including dethatching and regular irrigation.
Special Characteristics
Excellent wear recovery due to rhizomes; soft texture; high aesthetic value; susceptible to leaf spot and dollar spot; low salt tolerance; excellent for home lawns and sports fields in cool climates.
Ecological Information
Introduced/Naturalized in North America; provides cover for small mammals; highly effective at soil stabilization and erosion control on slopes; often mixed with Perennial Ryegrass or Fine Fescue for biodiversity and resilience.