Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, subfamily Pooideae, tribe Poeae
Grass Category
Lawn/Turf Grass, Sports Turf
Variety / Cultivar
Standard blend (e.g., 'Midnight', 'Baron')
Hardiness Zones
USDA Hardiness Zones 3 to 7, excellent cold tolerance, moderate heat tolerance, goes dormant in prolonged summer heat.
About This Grass
Forms a dense, high-quality turf with medium-fine texture and rich dark green to blue-green color. Height ranges from 1.5 to 2.5 inches when maintained, and up to 18-24 inches if unmowed with open, pyramidal seed heads.
Blade Characteristics
Blades are medium-width (2-4mm), flat to folded with prominent parallel veins and distinctive boat-shaped tips. Vernation is folded in the bud. Ligule is short and membranous; auricles are absent.
Root System
Moderately deep fibrous root system combined with extensive rhizomes. Forms a very dense sod, moderate to high thatch tendency, slow to moderate establishment speed.
Growing Information
Origin Region
Europe and Northern Asia; widely naturalized and cultivated across North America and temperate regions worldwide
Growth Habit
Rhizomatous, spreading underground via aggressive underground stems to form a dense sod
Sunlight & Water Needs
Requires full sun (minimum 6-8 hours) for best performance, moderate to high water needs, enters summer dormancy during severe drought.
Mowing & Maintenance
Mow at 2.0 to 3.0 inches. Medium to high maintenance level, requires regular fertilization (3-4 lbs N per 1000 sq ft per year) and occasional dethatching/aeration.
Special Characteristics
Excellent wear tolerance and self-healing via rhizomes, moderate shade tolerance, good disease resistance depending on cultivar, superior winter color retention compared to warm-season grasses.
Ecological Information
Introduced species in North America, provides good soil stabilization and turf cover, commonly mixed with Perennial Ryegrass and Fine Fescues.