Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, subfamily Pooideae
Grass Category
Lawn/Turf Grass, Sports Turf
Variety / Cultivar
General species type (common turf cultivars include 'Midnight', 'Bewitched')
Hardiness Zones
USDA Hardiness Zones 3 to 7, exceptionally cold-hardy, performs best in northern temperate climates.
About This Grass
Forms a lush, dense, medium-fine textured turf with rich dark to blue-green color. Mown height typically 1.5 to 2.5 inches, unmowed height reaches 18 to 24 inches with pyramidal panicle seed heads.
Blade Characteristics
Medium-fine width (2-3mm), flat to folded shape with distinctive boat-shaped tips. Vernation is folded in the bud. Color ranges from medium to dark green or blue-green. Ligule is short and membranous, auricles absent.
Root System
Moderately deep fibrous root system with strong rhizomes. Moderate thatch tendency under high nitrogen and water. Slow to moderate establishment from seed, but excellent long-term dense turf recovery.
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 extensive root-like stems to form a dense sod
Sunlight & Water Needs
Requires full sun (minimum 6-8 hours daily) with moderate to high water needs. Good cold-induced winter dormancy drought tolerance, but goes dormant in prolonged summer heat/drought.
Mowing & Maintenance
Mow at 2.0 to 3.0 inches. Medium to high maintenance level requiring regular fertilization (3-4 lbs N/1000 sq ft/year), periodic aeration, and irrigation during dry spells.
Special Characteristics
Excellent wear tolerance and self-repair via rhizomes. Good cold tolerance, moderate shade tolerance, prone to summer patch and dollar spot under stress, excellent for home lawns and athletic fields.
Ecological Information
Introduced to North America by European settlers. Provides good erosion control and soil stabilization through dense sod. Often blended with perennial ryegrass and fine fescues.