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
Midnight (referenced as a common high-quality cultivar)
Hardiness Zones
USDA Zones 2-7; excellent cold tolerance; enters dormancy during hot, dry periods; thrives in cool, moist climates.
About This Grass
A dense, low-growing grass with a distinct dark blue-green color. It forms a high-quality, lush carpet. Unmowed, it reaches 12-24 inches with open, airy panicle seed heads. Texture is medium-to-fine.
Blade Characteristics
Width: 2-4mm (medium); Shape: V-shaped or flat; Tip: Boat-shaped (keeled); Color: Dark blue-green; Vernation: Folded; Ligule: Very short, membranous; Auricles: Absent; Collar: Narrow and divided.
Root System
Moderately deep fibrous root system complemented by extensive rhizomes. Forms heavy thatch; excellent sod-forming ability; moderate-to-slow establishment from seed.
Growing Information
Origin Region
Native to Europe, Northern Asia, and the mountains of Morocco and Algeria; widely adapted to temperate climates globally.
Growth Habit
Rhizomatous (spreading via underground stems), forming a dense, uniform sod with a moderate rate of spread.
Sunlight & Water Needs
Full Sun preferred (6+ hours); moderate shade tolerance; requires consistent moisture; high water needs during summer heat; pH preference 6.0-7.0.
Mowing & Maintenance
Ideal height 1.5 to 2.5 inches; frequent mowing required; high fertilization (3-5 lbs N per 1000 sq ft/year); requires periodic dethatching and aeration; high maintenance level.
Special Characteristics
Excellent wear tolerance and recovery due to rhizomes; susceptible to leaf spot and dollar spot; moderate salt tolerance; iconic 'blue' hue; primary grass for athletic fields in cool climates.
Ecological Information
Introduced and naturalized in North America; provides forage for livestock and wildlife; excellent soil stabilization; used in mixes with Perennial Ryegrass and Fine Fescue.