Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, Subfamily Pooideae, Tribe Poeae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Indeterminate common type based on photo; potentially 'Midnight' or similar improved lawn variety given color and density
Hardiness Zones
USDA Zones 2-7; Excellent cold tolerance; enters summer dormancy during extreme heat; widely used in the northern transition zone.
About This Grass
A medium-textured turfgrass that forms a thick, carpet-like lawn. It features a rich dark-green color and produces narrow, upright seed heads (panicles) if left unmowed. In the photo, it shows characteristic boat-shaped leaf tips and dense tillering alongside white clover.
Blade Characteristics
Width: 2-4mm (medium); Shape: Folded in bud; Tip: Distinctive boat-shaped (keeled) tip; Color: Dark green to blue-green; Ligule: Short, membranous, and trancate; Auricles: Absent; Collar: Narrow to medium, glabrous.
Root System
Moderately shallow fibrous root system supported by extensive rhizomes. Forms high thatch but provides excellent sod strength and recovery from wear. Slow to establish from seed compared to ryegrass.
Growing Information
Origin Region
Native to Europe, North Asia, and the mountains of North Africa; widely naturalized across North America
Growth Habit
Rhizomatous (spreading via underground stems), forming a dense, durable sod with a moderate rate of spread
Sunlight & Water Needs
Preference: Full Sun (6+ hours); Water: High (requires regular irrigation to prevent dormancy during summer drought); Soil: Prefers well-drained, fertile soils with pH 6.0-7.0.
Mowing & Maintenance
Mowing height: 2.0 to 3.5 inches; Frequency: Weekly during peak spring/fall growth; Fertilization: 2-4 lbs N per 1,000 sq ft annually; Maintenance Level: High.
Special Characteristics
Excellent wear tolerance and recovery due to rhizomes; good ability to crowd out weeds when dense; moderate susceptibility to leaf spot and dollar spot; poor shade tolerance compared to fescues.
Ecological Information
Introduced and naturalized in North America; provides forage for various wildlife; effective for soil stabilization in temperate climates; often mixed with Perennial Ryegrass or Fine Fescue for diverse turf blends.