Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, subfamily Pooideae, tribe Poeae
Grass Category
Lawn/Turf Grass, Sports Turf, Golf Course Grass
Variety / Cultivar
Standard Northern Blend Cultivars (e.g., 'Midnight', 'Bewitched')
Hardiness Zones
USDA Hardiness Zones 3-8, excellent cold tolerance, moderate heat tolerance, goes dormant or semi-dormant during intense summer heat.
About This Grass
Forms a dense, high-quality turf with medium-fine texture and rich dark green to blue-green color. Reaches 18-24 inches if unmowed, but maintained at 1.5-2.5 inches. Produces open, pyramid-shaped panicle seed heads at maturity.
Blade Characteristics
Medium-fine width (2-3mm), flat to V-shaped blades with distinct boat-shaped tips and prominent parallel veins. Folded in the bud (vernation). Membranous ligule with no auricles.
Root System
Moderate depth fibrous root system with extensive underground rhizomes. Forms a dense, tough sod that establishes relatively slowly from seed but recovers well from wear.
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 aggressive horizontal shoots to form a dense, uniform sod
Sunlight & Water Needs
Requires full sun (minimum 6-8 hours daily), moderate to high watering needs, moderate drought tolerance entering dormancy during severe dry spells, prefers well-drained fertile soils with a pH of 6.0 to 7.0.
Mowing & Maintenance
Maintain at 1.5 to 2.5 inches. Requires regular mowing, medium-high fertilization (3-5 lbs N per 1000 sq ft per year), occasional dethatching due to dense rhizome production, and moderate maintenance overall.
Special Characteristics
Good wear tolerance and excellent self-repairing ability via rhizomes. Susceptible to summer patch, dollar spot, and leaf spot. High traffic tolerance, poor shade tolerance compared to fescues.
Ecological Information
Introduced species in North America. Provides good soil stabilization and erosion control due to dense root and rhizome network. Frequently blended with perennial ryegrass and fine fescues.