Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, subfamily Pooideae, tribe Poeae
Grass Category
Lawn/Turf Grass, Sports Turf, Golf Course Grass
Variety / Cultivar
Common blend (such as 'Midnight' or 'Baron' types)
Hardiness Zones
USDA Hardiness Zones 3 to 7, tolerating cold winters exceptionally well. Goes into winter dormancy in colder regions and struggles in extreme prolonged summer heat without irrigation.
About This Grass
Forms a dense, high-quality turf with medium-fine texture and a rich dark green to blue-green color. Reaches up to 18-24 inches if unmowed, but maintained at 1.5-2.5 inches. Features open, pyramidal panicle seed heads at maturity.
Blade Characteristics
Medium-fine width (3-4mm), flat to folded shape with distinctive boat-shaped tips and prominent parallel veins giving a railroad-track appearance. Vernation is folded in the bud. Ligule is short and membranous, auricles are absent.
Root System
Moderate depth (6-12 inches) with extensive fibrous roots and aggressive rhizomes. Can develop a moderate thatch layer over time. Slow to establish from seed, but has excellent self-repairing wear recovery.
Growing Information
Origin Region
Europe, northern Asia, and parts of the mountains in North America; widely cultivated throughout cool-temperate regions worldwide.
Growth Habit
Aggressively rhizomatous, forming a dense, uniform sod and spreading via underground stems.
Sunlight & Water Needs
Requires full sun (minimum 6-8 hours daily) and moderate to high water needs. Has moderate drought tolerance, going dormant in extreme dry spells and greening up when moisture returns. Prefers well-drained, fertile soils with a pH of 6.0-7.0.
Mowing & Maintenance
Ideal mowing height is 2.0 to 3.0 inches. Requires regular mowing, moderate to high fertilization (3-5 lbs N per 1000 sq ft annually), periodic dethatching, and core aeration. Maintenance level is high.
Special Characteristics
Exceptional wear tolerance and heavy traffic recovery due to rhizomes. Good cold tolerance, moderate shade tolerance, prone to certain diseases like dollar spot and leaf spot under stress, excellent erosion control.
Ecological Information
Introduced to North America by European settlers. Provides low wildlife foraging value compared to native prairie grasses, but offers soil stabilization, dust control, and urban heat island mitigation. Frequently blended with Perennial Ryegrass and Fine Fescue.