Kentucky Bluegrass
Poa pratensis · Cool-season, perennial, C3 grass
AI-generated identification · may be incorrect
Grass Category
Lawn/Turf Grass, Sports Turf, Golf Course Grass
Hardiness Zones
Thrives in USDA Hardiness Zones 3 through 7; excellent cold tolerance, moderate heat tolerance; susceptible to summer stress in southern transition zones
Grass Family
Poaceae, subfamily Pooideae, tribe Poeae
Variety / Cultivar
Midnight (known for dark blue-green color and high density)
About This Grass
Forms a dense, high-quality turf with a vibrant medium-to-dark green color, fine to medium texture, and upright growth habit when maintained; reaches 18 to 24 inches if unmowed with open, pyramidal panicle seed heads
Blade Characteristics
Blades are medium-width (2-4mm), flat with distinct parallel sides and characteristic boat-shaped tips; folded in the bud (vernation); medium to dark green with prominent parallel veins; membranous ligule and absent auricles
Root System
Moderately deep fibrous root system complemented by aggressive underground rhizomes; moderate establishment speed from seed; forms a very dense sod with a moderate to high thatch-forming tendency
Growing Information
Origin Region
Europe and Northern Asia; widely naturalized and cultivated across North America and cool temperate regions worldwide
Growth Habit
Rhizomatous, spreading extensively via underground stems to form a dense, uniform sod and turf mat
Sunlight & Water Needs
Requires full sun (minimum 6-8 hours daily); high water needs during hot, dry periods to maintain active growth; enters summer dormancy under severe drought conditions; prefers well-drained fertile soils with a pH of 6.0 to 7.0
Mowing & Maintenance
Ideal mowing height ranges from 2.0 to 3.5 inches; moderate to high maintenance level requiring regular mowing, frequent fertilization (3-5 lbs N per 1000 sq ft per year), periodic aeration, and dethatching
Special Characteristics
Excellent traffic and wear tolerance due to aggressive self-repairing rhizomes; moderate shade tolerance; susceptible to diseases like dollar spot, summer patch, and leaf spot under high humidity and improper management; superior winter color retention compared to warm-season grasses
Ecological Information
Introduced species in North America; provides soil stabilization, erosion control, and high aesthetic value for landscapes and sports fields; commonly blended with perennial ryegrass and fescues for enhanced turf resilience