Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, subfamily Pooideae, tribe Poeae
Grass Category
Lawn/Turf Grass and Sports Turf
Variety / Cultivar
Standard or common cultivars used for general lawns and turf
Hardiness Zones
USDA Hardiness Zones 3 through 7; excellent cold tolerance, moderate heat tolerance; goes dormant and turns brown during severe summer heat or drought
About This Grass
Forms a dense, fine-to-medium textured turf with an attractive dark to medium green color; spreads via aggressive rhizomes to self-repair; height reaches 18 to 24 inches if unmowed, but maintained at 1.5 to 2.5 inches; produces open, pyramidal panicle seed heads at maturity
Blade Characteristics
Medium-fine width (2-4mm), flat to folded shape, distinctive boat-shaped tips, bright to medium green color, folded in the bud (vernation), prominent parallel veins with two clear translucent lines on either side of the midrib, membranous ligule, and absent auricles
Root System
Moderately deep fibrous root system complemented by strong underground rhizomes; forms a very dense sod that holds soil exceptionally well; moderate establishment speed from seed, slow to germinate
Growing Information
Origin Region
Europe and northern Asia; widely naturalized and cultivated across North America and temperate regions worldwide
Growth Habit
Rhizomatous, spreading underground via extensive underground stems to form a dense, uniform turf and sod
Sunlight & Water Needs
Requires full sun (minimum 6 hours daily, performs best with 8+ hours); moderate to high water needs; moderate drought tolerance by entering summer dormancy; prefers well-drained fertile soils with a pH of 6.0 to 7.0
Mowing & Maintenance
Ideal mowing height is 2.0 to 3.0 inches; regular weekly mowing during peak growing season; high fertilizer requirement (3-5 lbs N per 1000 sq ft per year); requires regular aeration and occasional dethatching; high overall maintenance level
Special Characteristics
Excellent wear tolerance and traffic recovery due to rhizomes; moderate disease resistance (susceptible to leaf spot, dollar spot, and summer patch); good cold and winter color retention compared to warm-season grasses; superb erosion control
Ecological Information
Introduced species in North America; provides moderate wildlife habitat and ground cover; forms dense stands that can outcompete some weeds; frequently blended with perennial ryegrass and fine fescues for professional and residential turf