Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, subfamily Pooideae
Grass Category
Lawn/Turf Grass, Sports Turf, Golf Course Grass
Variety / Cultivar
Common blend, often including elite cultivars like 'Midnight' or 'Compact', known for dark green color and dense turf formation
Hardiness Zones
USDA Hardiness Zones 3 through 7, excellent cold tolerance, goes dormant and turns brown in extreme winter cold, performs well in northern regions and the upper transition zone.
About This Grass
Forms a dense, high-quality turf with medium-fine texture and a rich medium to dark green color. Height ranges from 1.5 to 2.5 inches when maintained, and can reach 18 to 24 inches if unmowed. Produces pyramidal panicle seed heads at maturity.
Blade Characteristics
Medium-fine blades (2-4mm width) with typical boat-shaped tips, folded in the bud (vernation), smooth texture with prominent parallel veins, membranous ligule, and absent auricles.
Root System
Moderately deep fibrous root system combined with extensive underground rhizomes. Moderate establishment speed, forms a very dense sod, and exhibits a moderate to high tendency to produce thatch.
Growing Information
Origin Region
Europe and Northern Asia, widely naturalized across North America and well adapted to northern temperate climates
Growth Habit
Rhizomatous, spreading underground via aggressive creeping rhizomes to form a dense, uniform turf mat
Sunlight & Water Needs
Requires full sun (minimum 6-8 hours daily) with moderate to high water needs. Has moderate drought tolerance, entering dormancy during severe dry spells, and prefers well-drained fertile soils with a pH of 6.0 to 7.0.
Mowing & Maintenance
Ideal mowing height is 2.0 to 3.0 inches. Requires regular mowing frequency, medium-high fertilization (3-4 lbs N per 1000 sq ft annually), periodic dethatching and core aeration, and is classified as a high-maintenance turf.
Special Characteristics
Excellent wear tolerance and self-repairing capability due to rhizomes. Good winter color retention in milder cool climates, but susceptible to summer patch, dollar spot, and leaf spot if improperly managed.
Ecological Information
Introduced species widely used for erosion control, residential lawns, and sports fields. Provides minimal wildlife food source compared to native prairies, but offers good soil stabilization and water filtration in urban landscapes.