Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, Subfamily Pooideae, Tribe Poeae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common or Elite variety (e.g., Midnight or Baron) based on typical lawn usage
Hardiness Zones
USDA Zones 2-7; excellent cold tolerance but poor performance in the deep South due to heat sensitivity.
About This Grass
A medium-textured, dark-green turfgrass. Grows 12-24 inches if left unmowed, with characteristic pyramidal or open-panicled seed heads. It forms a lush, uniform mat that goes dormant in high heat.
Blade Characteristics
Fine to medium width (2-4mm), V-shaped or flat leaves with a distinctive boat-shaped (keeled) tip. Vernation is folded in the bud; ligule is short and membranous; auricles are absent.
Root System
Relatively shallow fibrous root system supplemented by strong rhizomes. High thatch-forming tendency; moderate establishment speed from seed.
Growing Information
Origin Region
Native to Europe, North Asia, and North Africa; widely adapted to temperate regions of North America
Growth Habit
Rhizomatous (spreading via underground stems), forming a dense, self-repairing sod
Sunlight & Water Needs
Prefers Full Sun (6+ hours), moderate shade tolerance. High water requirements; enters summer dormancy during drought to survive.
Mowing & Maintenance
Ideal height 2.5 to 3.5 inches. High maintenance: requires 2-4 lbs Nitrogen per 1000 sq ft annually, regular aeration, and dethatching.
Special Characteristics
Excellent wear tolerance and recovery due to rhizomes; susceptible to leaf spot, melting out, and necrotic ring spot.
Ecological Information
Introduced/Naturalized status in North America; provides soil stabilization and high-quality forage for wildlife; often blended with Perennial Ryegrass or Fine Fescue.