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 (Fairways/Tees)
Variety / Cultivar
Midnight (example of a common high-quality elite variety)
Hardiness Zones
USDA Zones 2-7. Excellent cold tolerance; enters winter dormancy; struggles in the high heat of southern Zone 8 and above.
About This Grass
A dark green, high-density turf grass that forms a lush 'carpet' appearance. It grows 12-24 inches unmowed but thrives at low heights. Known for its rich color and excellent dormancy recovery.
Blade Characteristics
Blade width is fine to medium (2-4mm). Features a distinctive V-shaped fold and a 'boat-shaped' tip. Vernation is folded in the bud; ligule is short and membranous; auricles are absent.
Root System
Moderate depth with extensive rhizomes. Forms a heavy thatch layer easily. Establishment is slow (2-3 weeks for germination), but it creates a very stable, durable sod.
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
Requires Full Sun (6-8 hours minimum) for best performance. High water needs; poor drought resistance but excellent drought dormancy (can survive but turns brown). Prefers pH 6.0-7.0.
Mowing & Maintenance
Ideal height 2.0-3.5 inches. Requires frequent mowing and high fertilization (3-5 lbs N per 1000 sq ft/year). High maintenance level requiring regular dethatching and aeration.
Special Characteristics
Exceptional wear tolerance and recovery due to rhizomes. Good disease resistance in elite cultivars. Poor shade tolerance and moderate salt tolerance.
Ecological Information
Introduced and naturalized in North America. Provides habitat for small insects and soil stabilization. Often mixed with Perennial Ryegrass or Fine Fescue for improved diversity and shade tolerance.