Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, subfamily Pooideae, tribe Poeae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Mixed turf-type cultivars commonly used for residential lawns
Hardiness Zones
Thrives in USDA Hardiness Zones 3 through 7, tolerating cold winters well but going semi-dormant or requiring irrigation during extreme summer heat in transition zones.
About This Grass
A dense, rich green turf grass that responds exceptionally well to mowing, producing classic contrasting lawn stripes as seen in the image. Maintained at a medium-low height, it forms a thick carpet with a fine to medium texture.
Blade Characteristics
Medium-narrow width (2-3mm), flat to folded shape with distinct boat-shaped tips. Vernation is folded in the bud. Leaves feature parallel veins with a prominent midrib on the underside.
Root System
Moderately deep fibrous root system combined with vigorous underground rhizomes, creating a tough, resilient sod that recovers well from traffic, though establishment from seed can be slow.
Growing Information
Origin Region
Europe and Northern Asia; widely naturalized and cultivated across North America, performing best in cool, humid and semi-arid regions
Growth Habit
Rhizomatous with aggressive underground spreading, forming a dense, uniform sod
Sunlight & Water Needs
Requires full sun to partial shade (minimum 4 to 6 hours of direct sunlight), moderate to high watering needs during dry spells, and moderate drought dormancy.
Mowing & Maintenance
Ideal mowing height ranges from 2.0 to 3.0 inches. Requires regular mowing, moderate to high fertilization (3-4 lbs N per 1000 sq ft annually), and periodic aeration to manage thatch; overall maintenance level is Medium-High.
Special Characteristics
Excellent wear tolerance and self-repairing capabilities due to rhizomes, good cold tolerance, moderate drought recovery, and forms a dense weed-resistant turf when properly maintained.
Ecological Information
Introduced to North America by European settlers. Provides standard lawn ecosystem services, stabilizes topsoil against erosion, and commonly blended with perennial ryegrass and fine fescues.