Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 pathway; classic transition zone and northern climate grass
Grass Family
Poaceae, Subfamily Pooideae, Tribe Poeae
Grass Category
Lawn/Turf Grass, Sports Turf, Golf Course Fairway/Rough
Variety / Cultivar
Common lawn variety (likely a mixture including cultivars like 'Midnight' or 'Baron' based on dark green-blue hue)
Hardiness Zones
USDA Zones 2-7; excellent cold tolerance; enters winter dormancy and turns brown in extreme cold; poor performance in deep South heat.
About This Grass
A medium-textured, dark-green to blue-green perennial grass. Forms a plush, carpet-like turf which remains attractive under high maintenance. Seed heads are open panicles, though rarely seen in mowed lawns.
Blade Characteristics
Blade width is medium (2-4mm). Features a distinct V-shaped or boat-shaped leaf tip. Vernation is folded in the bud. Ligule is short and membranous; auricles are absent. Mid-rib is visible with two clear 'skating rink' lines.
Root System
Relatively shallow fibrous root system supplemented by aggressive underground rhizomes. High thatch tendency due to rhizome density; moderate establishment speed from seed.
Growing Information
Origin Region
Native to Europe, North Asia, and the mountains of Morocco and Algeria; highly adapted to cool, humid climates
Growth Habit
Rhizomatous (spreading underground); forms a thick, dense sod with excellent recuperative ability
Sunlight & Water Needs
Prefers full sun (minimum 6 hours). Low shade tolerance. Requires consistent moisture (1 inch per week). Susceptible to dormancy during extreme summer heat/drought.
Mowing & Maintenance
Mowing height 2.0 to 3.5 inches. Requires frequent mowing during peak spring/fall growth. 3-5 lbs Nitrogen per 1000 sq ft per year. High maintenance level.
Special Characteristics
Excellent traffic tolerance and wear recovery due to rhizomes. Susceptible to summer patch, dollar spot, and necrotic ring spot. Highly prized for its soft texture and uniformity.
Ecological Information
Introduced and naturalized in North America. Provides erosion control via dense sod; high water filtration value. Often mixed with Perennial Ryegrass or Fine Fescue for diversity.