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-type and turf-type blends (e.g., 'Midnight', 'Bewitched')
Hardiness Zones
Thrives in USDA Hardiness Zones 3 through 7. Excellent cold tolerance, goes dormant and turns brown during severe summer heat or drought.
About This Grass
Fine to medium-textured turfgrass with an upright growth habit, vibrant medium to dark green or blue-green color. Forms a very dense, carpet-like sward. Reaches 18 to 24 inches if left unmowed. Produces open, pyramidal panicle seed heads at maturity.
Blade Characteristics
Blades are medium width (2-4mm), flat or folded in the bud (Vernation: folded), with characteristic boat-shaped tips. Prominent parallel veins and a distinct midvein. Ligule is short and membranous, auricles are absent, and the collar is broad and continuous.
Root System
Moderately deep fibrous root system with extensive branching rhizomes. Forms a dense sod, high thatch-forming tendency under high maintenance, moderate establishment speed from seed.
Growing Information
Origin Region
Native to Europe, northern Asia, and the mountains of North America; widely cultivated throughout cool and temperate regions globally.
Growth Habit
Rhizomatous with aggressive underground stems, forming a dense, uniform turf mat and sod.
Sunlight & Water Needs
Requires full sun (minimum 6 hours direct sunlight daily) and moderate to high moisture levels. Moderate drought tolerance via summer dormancy, prefers well-drained loamy soils with a pH of 6.0 to 7.0.
Mowing & Maintenance
Ideal mowing height is 2.0 to 3.0 inches. Requires regular mowing, high fertilization (2-4 lbs N per 1000 sq ft per year), periodic dethatching and core aeration, and high overall maintenance level.
Special Characteristics
High wear tolerance and excellent self-repairing capability via rhizomes. Good cold tolerance, moderate shade tolerance, slow to germinate from seed, excellent erosion control.
Ecological Information
Widely naturalized in North America. Provides good soil stabilization and erosion control. Often blended with Perennial Ryegrass and Fine Fescues to improve disease resistance and establishment speed.