Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
AI-generated identification · may be incorrect
Grass Category
Lawn/Turf Grass, Sports Turf
Hardiness Zones
USDA Hardiness Zones 3 to 7, excellent cold tolerance down to -30F or lower, but struggles with extreme summer heat unless irrigated.
Grass Family
Poaceae, subfamily Pooideae, tribe Poeae
Variety / Cultivar
'Midnight' or similar dark green elite cultivar, known for excellent color and disease resistance
About This Grass
Forms a dense, medium-textured turf with an attractive rich green to blue-green color. Height ranges from 1.5 to 3 inches when maintained. Produces open, pyramid-shaped panicle seed heads at maturity if left unmowed.
Blade Characteristics
Medium width (2-4mm), flat to folded shape with distinctive boat-shaped tips. Color ranges from medium to dark green or blue-green. Folded vernation in the bud. Prominent parallel veins with a smooth texture.
Root System
Moderate depth fibrous root system with aggressive rhizomes. Forms a very dense thatch layer if not managed properly. Slow to germinate and establish, but provides excellent self-repairing wear recovery and sod strength.
Growing Information
Origin Region
Europe and Northern Asia, naturalized throughout North America, performs best in cool, humid to semi-arid regions
Growth Habit
Rhizomatous, spreading extensively via underground runners to form a dense, uniform sod
Sunlight & Water Needs
Requires full sun (minimum 6 hours of direct sunlight), though some cultivars show moderate shade tolerance. High watering needs to maintain green color during dry periods; enters summer dormancy under severe drought.
Mowing & Maintenance
Ideal mowing height is 2.0 to 3.0 inches. Medium to high maintenance level requiring regular fertilization (3-4 lbs N per 1000 sq ft annually), periodic aeration, and dethatching.
Special Characteristics
Good wear tolerance and excellent self-repair due to rhizomes. Susceptible to certain diseases like dollar spot and summer patch, but modern cultivars have improved resistance. Not salt-tolerant.
Ecological Information
Introduced species in North America. Provides good soil stabilization and erosion control due to its dense root and rhizome network. Often blended with perennial ryegrass and fine fescues for home lawns.