Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, subfamily Pooideae
Grass Category
Lawn/Turf Grass and Sports Turf
Variety / Cultivar
Common blend or standard turf cultivars
Hardiness Zones
Thrives in USDA Hardiness Zones 3 to 7, exhibiting excellent cold tolerance and winter hardiness, though it can struggle with extreme summer heat in the deep southern transition zone.
About This Grass
Forms a dense, medium-textured turf with rich green to blue-green color. Height ranges from 1.5 to 2.5 inches when maintained, but can grow up to 18-24 inches if unmowed. Produces panicle seed heads at maturity.
Blade Characteristics
Medium blade width (2-4mm), folded in the bud (vernation), with distinctive boat-shaped tips and prominent parallel veins giving a tramline appearance. Membranous ligule and no auricles.
Root System
Moderately deep fibrous root system combined with aggressive underground rhizomes, providing excellent sod strength and moderate thatch-forming tendencies. Medium establishment speed from seed.
Growing Information
Origin Region
Europe and Northern Asia; widely naturalized across North America and well-adapted to temperate regions
Growth Habit
Rhizomatous, spreading extensively via underground stems to form a dense, uniform sod
Sunlight & Water Needs
Requires full sun (minimum 6-8 hours daily) and moderate to high moisture for optimal growth. Moderate drought tolerance, entering summer dormancy during extended dry periods.
Mowing & Maintenance
Maintain at 2.0 to 3.5 inches height. Requires medium-high maintenance including regular fertilization (3-4 lbs N per 1000 sq ft annually), frequent mowing, and periodic aeration or dethatching.
Special Characteristics
Exceptional traffic and wear tolerance with superior self-repairing capabilities due to rhizomes. Good cold and disease resistance, though susceptible to dollar spot and leaf spot under high humidity.
Ecological Information
Introduced species in North America widely used for turfgrass. Provides good soil stabilization and erosion control, often blended with perennial ryegrass and fine fescues in regional turf mixes.