Kentucky Bluegrass
Poa pratensis · Cool-season (C3), Perennial
Grass Family
Poaceae, subfamily Pooideae, tribe Poeae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common or Elite-type (e.g., Midnight, Baron)
Hardiness Zones
USDA Zones 2–7; excellent cold tolerance; poor heat tolerance in deep South; goes dormant in extreme heat or cold.
About This Grass
A dense, low-growing turf grass with a distinct dark green to blue-green color. It creates a lush carpet-like texture and enters semi-dormancy in high summer heat. Features small, open panicle seed heads if left unmowed.
Blade Characteristics
Fine to medium width (2-4mm), V-shaped or flat, distinctive 'boat-shaped' leaf tips, blue-green color, folded vernation, with a short membranous ligule and no auricles.
Root System
Moderately deep fibrous root system with extensive rhizomes; high thatch-forming tendency; slower establishment from seed (21+ days) compared to ryegrass.
Growing Information
Origin Region
Europe and Northern Asia; widely naturalized in North America and temperate climates globally
Growth Habit
Rhizomatous; spreads via underground stems to form a dense, knit sod
Sunlight & Water Needs
Full Sun preferred (6+ hours), moderate shade tolerance. High water needs; requires consistent moisture to prevent summer dormancy; prefers well-drained soil, pH 6.0-7.0.
Mowing & Maintenance
Ideal height 2.5–3.5 inches; weekly mowing; 2–4 lbs N per 1000 sq ft annually; requires regular aeration and occasional dethatching; medium to high maintenance.
Special Characteristics
Excellent wear recovery due to rhizomes; good salt tolerance in certain cultivars; susceptible to leaf spot, melting out, and necrotic ring spot.
Ecological Information
Introduced/Naturalized (non-native in US); provided cover for small wildlife; excellent soil stabilization due to sod-forming habit; often mixed with Fine Fescue or Perennial Ryegrass.