Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, Subfamily Pooideae, Tribe Poeae
Grass Category
Lawn/Turf Grass, Sports Turf, Golf Course Grass
Variety / Cultivar
Common or Elite-type Bluegrass (e.g., Midnight, Baron)
Hardiness Zones
USDA Zones 2-7; excellent cold tolerance; moves into semi-dormancy in hot, dry summers
About This Grass
A dense, high-quality turf with a distinctive dark blue-green color. It grows 1-3 feet if unmowed but is traditionally kept short. Forms a smooth, uniform carpet with fine to medium texture.
Blade Characteristics
Blade width 2-4mm (medium); flat or slightly V-shaped; distinctive boat-shaped (keeled) tip. Vernation is folded in the bud. Ligule is short, membranous, and truncate; auricles are absent.
Root System
Moderately shallow fibrous root system with extensive horizontal rhizomes. High thatch tendency. Slower to establish from seed (21+ days) but provides excellent sod strength and recovery.
Growing Information
Origin Region
Native to Europe, North Asia, and Northern Africa; well-adapted to Northern US and Canada
Growth Habit
Rhizomatous (spreading underground), forming a dense, self-repairing sod mat
Sunlight & Water Needs
Requires Full Sun (6+ hours); poor shade tolerance. High water needs (1-1.5 inches/week). Needs well-drained soil, pH 6.0-7.0. Moderate drought tolerance (enters dormancy to survive).
Mowing & Maintenance
Ideal height 2.0-3.5 inches; mow weekly. Fertilization 2-4 lbs Nitrogen/1000 sq ft/year. Requires occasional dethatching and core aeration. High maintenance level.
Special Characteristics
Excellent wear tolerance and recovery due to rhizomes; susceptible to Dollar Spot and necrotic ring spot; low salt tolerance; high aesthetic value for home lawns.
Ecological Information
Introduced/Naturalized in North America; provides forage for various lepidoptera larvae; excellent soil stabilizer for erosion control; often blended with Perennial Ryegrass or Fine Fescue.