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
USDA Hardiness Zones 3 to 7, excellent cold tolerance, moderate heat tolerance, often struggles in extreme southern transition zones without heavy irrigation.
Grass Family
Poaceae, subfamily Pooideae, tribe Poeae
Variety / Cultivar
General species (commonly cultivars like 'Midnight' or 'Baron')
About This Grass
Forms a lush, dense, dark green to blue-green turf with medium fine texture. Grows 18 to 24 inches tall 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 with distinctive boat-shaped tips. Dark green to blue-green color. Rolled in the bud (vernation). Membranous ligule with no auricles and a broad collar.
Root System
Moderately deep fibrous root system combined with aggressive underground rhizomes. Forms a dense sod, though establishment speed from seed is slow. Moderate drought tolerance via going into summer dormancy.
Growing Information
Origin Region
Europe and Northern Asia, widely naturalized and cultivated across North America and temperate regions worldwide
Growth Habit
Rhizomatous, spreading extensively via underground stems to form a dense, uniform turf mat
Sunlight & Water Needs
Requires full sun (at least 6-8 hours daily), moderate to high water needs during active growth, and prefers well-drained fertile soils with a pH of 6.0 to 7.0.
Mowing & Maintenance
Ideal mowing height is 1.5 to 2.5 inches. Requires moderate to high maintenance, regular fertilization (3-4 lbs N per 1000 sq ft per year), periodic dethatching, and aeration.
Special Characteristics
Excellent traffic and wear tolerance due to self-repairing rhizomes, good winter color retention in milder climates, prone to certain diseases like dollar spot and leaf spot under stress.
Ecological Information
Introduced species in North America, provides standard wildlife forage and lawn habitat, excellent for erosion control on slopes due to dense root and rhizome matrix, frequently blended with perennial ryegrass and fescues.