Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
AI-generated identification · may be incorrect
Grass Category
Lawn/Turf Grass, Sports Turf
Hardiness Zones
USDA Hardiness Zones 3 to 7, exhibits excellent cold tolerance but struggles in extreme southern heat.
Grass Family
Poaceae, subfamily Pooideae, tribe Poeae
Variety / Cultivar
Standard turf-type blends (e.g., 'Midnight', 'Bewitched')
About This Grass
Dense, fine-to-medium textured turfgrass with a rich dark green to blue-green color. Forms a tight sod with upright shoots. Height ranges from 1.5 to 3 inches when maintained, and up to 18-24 inches if left unmowed with open, pyramidal seed heads.
Blade Characteristics
Blades are medium in width (2-4mm), flat to folded with prominent parallel veins and a distinctive boat-shaped tip. Vernation is folded in the bud. Ligule is short and membranous, with no auricles.
Root System
Moderately deep fibrous root system combined with aggressive underground rhizomes. Moderate to high thatch-forming tendency under high fertility and moisture. Slow to moderate establishment speed from seed.
Growing Information
Origin Region
Europe and Northern Asia; widely cultivated throughout the northern United States and Canada
Growth Habit
Rhizomatous, forming a dense, uniform turf through underground spreading stems
Sunlight & Water Needs
Requires full sun (minimum 6-8 hours daily), moderate to high water needs during hot periods, and goes into summer dormancy if drought-stressed. Prefers well-drained fertile soils with a pH of 6.0 to 7.0.
Mowing & Maintenance
Mow at 2.0 to 3.0 inches height. High maintenance level requiring regular fertilization (3-4 lbs N per 1000 sq ft annually), frequent irrigation, periodic dethatching, and core aeration.
Special Characteristics
Exceptional wear tolerance and self-repairing capability via rhizomes. Good cold tolerance and winter color retention in milder cool climates. Susceptible to certain diseases like dollar spot and leaf spot under high humidity.
Ecological Information
Introduced species in North America widely used for erosion control, residential lawns, and sports facilities. Excellent sod-forming capabilities that stabilize soil and filter runoff.