Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, subfamily Pooideae
Grass Category
Lawn/Turf Grass, Sports Turf
Variety / Cultivar
Common or standard turf cultivars (e.g., 'Midnight', 'Bewitched')
Hardiness Zones
USDA Hardiness Zones 3 through 7 (performs best in northern regions and the cool humid/irrigated transition zone). Excellent cold tolerance.
About This Grass
Forms a fine to medium-textured, high-density, rich green to blue-green turf. Height ranges from 1.5 to 3 inches when maintained, and up to 18-24 inches if left unmowed with panicle seed heads.
Blade Characteristics
Medium width (2-4mm), flat to folded with distinct parallel veins and a prominent midrib. The tip is distinctly boat-shaped (prow-shaped). Vernation is folded in the bud. Ligule is short and membranous, auricles are absent.
Root System
Fibrous and rhizomatous root system with moderate depth (4-6 inches primarily, extending deeper). Forms a dense, tough sod. Tends to build moderate thatch under high fertilization.
Growing Information
Origin Region
Europe and Northern Asia; widely naturalized and cultivated across North America and temperate regions worldwide.
Growth Habit
Aggressively rhizomatous, forming a dense, uniform turf mat and sod.
Sunlight & Water Needs
Requires full sun (minimum 6-8 hours daily) for best performance, though some shade-tolerant cultivars exist. Requires regular watering (1 inch per week) and has moderate drought tolerance, going dormant during severe dry spells.
Mowing & Maintenance
Mow at 2.0 to 3.5 inches. Requires regular mowing, moderate to high fertilization (2-4 lbs N per 1000 sq ft annually), periodic dethatching, and aeration. High maintenance level overall.
Special Characteristics
Exceptional wear tolerance and self-repairing capability via rhizomes. Good traffic recovery, moderate shade tolerance depending on cultivar, excellent cold hardiness, and goes dormant during hot, dry summer periods.
Ecological Information
Introduced species in North America. Provides good soil stabilization and erosion control due to its dense rhizomatous root network. Frequently blended with Perennial Ryegrass and Fine Fescues.