Kentucky Bluegrass
Poa pratensis · Cool-season perennnial (C3)
Grass Family
Poaceae, Subfamily Pooideae, Tribe Poeae
Grass Category
Lawn/Turf Grass, Sports Turf, Golf Course Fairways
Variety / Cultivar
Common or Elite-type (e.g., 'Midnight' or 'Baron' styles based on dark green color and dense growth)
Hardiness Zones
USDA Zones 2-7; excellent cold tolerance; poor heat tolerance (goes dormant in summer if not irrigated).
About This Grass
A dark green, medium-to-fine textured grass with a soft feel. It forms a dense uniform turf and enters dormancy during extreme heat/drought but recovers quickly in fall. Seed heads are open, spreading panicles.
Blade Characteristics
Bades are 2-4mm wide (medium-fine); the most distinctive feature is the boat-shaped (keeled) leaf tip; vernation is folded; ligule is short and membranous; auricles are absent; color ranges from deep blue-green to dark green.
Root System
Moderately shallow fibrous root system with extensive rhizomes; forms high-quality sod but susceptible to thatch buildup; slower establishment from seed (2-3 weeks) compared to ryegrass.
Growing Information
Origin Region
Native to Europe, North Asia, and Morocco; widely naturalized across North America, performing best in temperate climates.
Growth Habit
Rhizomatous (spreading underground); forms a thick, dense, sod-forming mat that fills in bare spots via lateral underground stems.
Sunlight & Water Needs
Full sun preferred (6-8 hours); moderate to high water needs; poor shade tolerance compared to fescues; prefers well-drained soil with pH 6.0-7.0.
Mowing & Maintenance
Ideal height 2.5 to 3.5 inches; high maintenance; requires 3-5 lbs Nitrogen per 1000 sq ft annually; needs periodic dethatching and core aeration.
Special Characteristics
Excellent wear tolerance and recovery due to rhizomes; produces the highest quality aesthetic for home lawns; susceptible to Kentucky Bluegrass Rust, Summer Patch, and Dollar Spot.
Ecological Information
Introduced and naturalized in North America; provides forage for livestock and ground cover for small mammals; often mixed with Perennial Ryegrass and Fine Fescue for genetic diversity and shade adaptation.