Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, Subfamily Pooideae, Tribe Poeae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Generic / Common Kentucky Bluegrass (Commercial Mix)
Hardiness Zones
USDA Zones 3-7; excellent cold tolerance; poor heat tolerance in deep south; enters winter dormancy and may enter summer dormancy in high heat.
About This Grass
A medium-textured, dark-green turfgrass that forms a dense sod. It reaches 12-24 inches if unmowed, featuring an open, pyramid-shaped panicle seed head. It exhibits high density through tillering and rhizome production.
Blade Characteristics
Blade width 2-4mm (medium); flat or slightly V-shaped; distinctive boat-shaped (keeled) tip; dark blue-green color; vernation is folded in the bud; ligule is short and membranous; auricles are absent.
Root System
Moderately shallow fibrous root system with extensive horizontal rhizomes; forms thick thatch; high establishment speed from seed; exceptional sod-forming ability for wear recovery.
Growing Information
Origin Region
Europe, Northern Asia, and North Africa; naturalized throughout North America
Growth Habit
Rhizomatous (spreading underground), forming a dense, uniform sod with moderate rate of spread
Sunlight & Water Needs
Prefers Full Sun (6+ hours); moderate shade tolerance; requires 1 inch of water per week; goes dormant during severe drought to survive; prefers well-drained soil with pH 6.0-7.0.
Mowing & Maintenance
Recommeded height 2.0-3.5 inches; frequent mowing required during spring/fall peaks; 2-4 lbs Nitrogen per 1000 sq ft annually; high maintenance level due to water and fert needs.
Special Characteristics
Excellent wear tolerance and recovery due to rhizomes; susceptible to leaf spot, melting out, and necrotic ring spot; high aesthetic value for home lawns and sports fields.
Ecological Information
Introduced species in North America; provides soil stabilization via dense rhizome mats; used as a companion with Perennial Ryegrass and Fine Fescues in 'Northern Mixes'.