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 3-7; excellent cold tolerance, moderate heat tolerance, enters winter dormancy in colder climates
Grass Family
Poaceae, subfamily Pooideae
Variety / Cultivar
Midnight (known for dark blue-green color and high density)
About This Grass
Forms an exceptionally dense, high-quality turf with medium-fine texture and rich dark blue-green coloration; typical unmowed height reaches 18-24 inches, maintained at 1.5-2.5 inches; produces open panicle seed heads at maturity
Blade Characteristics
Medium-fine width (2-3mm), folded in the bud (vernation), flat or slightly folded shape with distinct boat-shaped tips and prominent parallel veins giving a tramline appearance; membranous ligule with absent auricles
Root System
Moderately deep fibrous root system combined with vigorous rhizomes; creates a dense, tough sod that recovers well from wear; moderate thatch tendency and slow to medium establishment rate from seed
Growing Information
Origin Region
Europe and Northern Asia; widely naturalized and cultivated across North America and temperate regions
Growth Habit
Rhizomatous, spreading underground via aggressive underground stems to form a dense, uniform turf mat
Sunlight & Water Needs
Requires full sun (minimum 6-8 hours daily); high water needs during hot periods for optimal growth, goes into summer dormancy under severe drought; prefers well-drained, fertile loamy soils with pH between 6.0 and 7.0
Mowing & Maintenance
Mow at 1.5 to 2.5 inches regularly; requires medium to high maintenance including 2-4 lbs N per 1000 sq ft annually, regular irrigation, annual aeration, and periodic dethatching
Special Characteristics
High traffic and wear tolerance due to self-repairing rhizomes; moderate disease susceptibility (susceptible to dollar spot, leaf spot, and summer patch); excellent drought recovery; good weed suppression ability
Ecological Information
Introduced species in North America; provides basic turf ecosystem services like soil stabilization and temperature reduction; commonly blended with Perennial Ryegrass and Fine Fescues for home lawns and sports fields