Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
AI-generated identification · may be incorrect
Grass Category
Lawn/Turf Grass, Sports Turf
Hardiness Zones
Thrives in USDA Hardiness Zones 3 to 7, exhibits high cold tolerance, but struggles with extreme summer heat unless irrigated.
Grass Family
Poaceae, subfamily Pooideae, tribe Poeae
Variety / Cultivar
Standard turf-type blend (e.g., 'Midnight', 'Baron')
About This Grass
Forms a dense, medium-textured turf with an attractive dark green to blue-green color. Mown height typically ranges from 1.5 to 2.5 inches, while unmown plants can reach 18 to 24 inches with open, pyramidal panicle seed heads.
Blade Characteristics
Fine to medium width (2-4mm), flat to folded with distinct boat-shaped tips and parallel sides. Vernation is folded in the bud. Ligule is short and membranous, auricles are absent, and the collar is narrow and distinct.
Root System
Moderately deep fibrous root system combined with extensive branching rhizomes. Forms a very dense sod, moderate establishment speed, and moderate thatch-forming tendency under high fertility.
Growing Information
Origin Region
Europe, northern Asia, and the mountains of North America; widely cultivated throughout cool temperate regions worldwide
Growth Habit
Rhizomatous, spreading aggressively via underground shoots to form a dense, uniform turf
Sunlight & Water Needs
Requires full sun (minimum 6-8 hours daily) for optimal growth, though some cultivars offer moderate shade tolerance. High watering needs to maintain active growth during summer; goes into summer dormancy under severe drought but recovers well. Prefers well-drained fertile soils with a pH of 6.0 to 7.0.
Mowing & Maintenance
Mow at 2.0 to 3.0 inches. Requires medium-high maintenance including regular fertilization (2-4 lbs N per 1000 sq ft annually), regular watering, and periodic dethatching and core aeration.
Special Characteristics
Excellent traffic and wear tolerance due to aggressive rhizomatous recovery. Good cold hardiness and winter color retention in milder cool-season zones. Susceptible to certain diseases like dollar spot, leaf spot, and summer patch.
Ecological Information
Introduced species in North America. Provides good soil stabilization, erosion control, and minor wildlife habitat. Commonly blended with Perennial Ryegrass and Fine Fescues in cool-season turf seed mixes.