Kentucky Bluegrass
Poa pratensis · Cool-season perennial, C3 photosynthesis
Grass Family
Poaceae, Subfamily Pooideae, Tribe Poeae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Generic / Common Kentucky Bluegrass (often found in 3-way mixes)
Hardiness Zones
USDA Zones 2-7; excellent cold tolerance; poor heat tolerance in deep south; goes dormant/brown in summer heat without water.
About This Grass
A dense, cool-season turfgrass with a rich green to blue-green color. It maintains a low-growing habit when mowed, but can reach 12-20 inches if left unmowed, producing panicle-type seed heads that are open and pyramid-shaped.
Blade Characteristics
Fine to medium width (2-4mm); V-shaped or flat; featuring a distinct boat-shaped tip; dark green color; folded vernation; membranous short ligule; no auricles; smooth collar.
Root System
Moderately shallow fibrous roots with extensive rhizomes; known for high thatch tendency and excellent sod-forming ability; moderate establishment speed from seed.
Growing Information
Origin Region
Native to Europe, Northern Asia, and parts of North Africa; widely adapted to temperate climates globally
Growth Habit
Rhizomatous (spreading via underground stems), forming a dense, uniform sod with high regenerative capacity
Sunlight & Water Needs
Full sun preferred (6-8 hours); moderate to high water needs; enters dormancy during severe drought; prefers well-drained fertile soil with pH 6.0-7.0.
Mowing & Maintenance
Ideal height 2.0-3.5 inches; weekly mowing; 2-4 lbs N per 1000 sq ft annually; requires periodic dethatching; medium to high maintenance level.
Special Characteristics
Excellent wear tolerance due to rhizomes; high self-repairing ability; susceptible to Necrotic Ring Spot and Summer Patch; poor shade tolerance.
Ecological Information
Introduced in North America; provides forage for various wildlife and insects; excellent at soil stabilization and preventing erosion; frequently mixed with Perennial Ryegrass or Fine Fescue for biodiversity.