Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, subfamily Pooideae
Grass Category
Lawn/Turf Grass, Sports Turf
Variety / Cultivar
Midnight (known for dark blue-green color and dense growth habit)
Hardiness Zones
USDA Hardiness Zones 3 to 7, excellent cold tolerance, moderate heat tolerance, often combined with tall fescue in the transition zone
About This Grass
Forms a dense, high-quality turf with a medium texture and rich blue-green color; grows 1.5 to 2.5 feet tall if unmowed, but maintained at 1.5 to 2.5 inches; produces panicle seed heads at maturity
Blade Characteristics
Medium-fine blades (2-4mm wide) with distinctive boat-shaped tips, folded vernation in the bud, prominent parallel veins creating a railroad-track appearance, and a short membranous ligule with no auricles
Root System
Moderate to deep fibrous root system with aggressive underground rhizomes, moderate thatch-forming tendency, slow establishment speed from seed, but forms an extremely tough, wear-resistant sod
Growing Information
Origin Region
Europe, Northern Asia, and parts of the mountains of North America; widely cultivated across temperate regions globally
Growth Habit
Rhizomatous, spreading extensively via underground stems to form a dense, uniform turf
Sunlight & Water Needs
Requires full sun (minimum 6-8 hours daily), moderate to high watering needs for optimal appearance, enters dormancy during severe drought, prefers well-drained fertile soils with a pH of 6.0 to 7.0
Mowing & Maintenance
Ideal mowing height from 2.0 to 3.0 inches, frequent mowing during peak spring/fall growth, requires moderate to high fertilization (3-4 lbs N per 1000 sq ft annually), regular dethatching and aeration, high maintenance level
Special Characteristics
Exceptional wear and traffic tolerance due to rhizomatous recovery, good cold hardiness, self-repairing turf, susceptible to summer patch and dollar spot if over-fertilized, excellent for home lawns and athletic fields
Ecological Information
Introduced species in North America, provides basic cover for urban wildlife, forms strong root mats that prevent soil erosion and filter runoff water, commonly blended with perennial ryegrass and fine fescues