Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, Subfamily Pooideae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common turf-type variety (potentially 'Midnight' or similar dark green elite cultivar)
Hardiness Zones
USDA Zones 2-7; excellent cold tolerance; poor heat tolerance (enters summer dormancy in hot climates).
About This Grass
A dense, medium-textured turfgrass with a characteristic dark green or blue-green color. It exhibits a uniform stand when mowed, with a vertical growth pattern and the ability to self-repair through its rhizome network.
Blade Characteristics
Fine to medium width (2-4mm); folded vernation in the bud; leaf tips are distinctly 'boat-shaped' (keeled); ligule is very short and membranous; auricles are absent.
Root System
Moderately shallow fibrous root system with extensive horizontal rhizomes; forms a thick, durable sod; moderate thatch tendency and slow to medium establishment from seed.
Growing Information
Origin Region
Native to Europe, North Asia, and the mountains of North Africa; well-adapted to temperate, cool-humid climates
Growth Habit
Rhizomatous (spreading via underground stems), form dense sod through aggressive lateral growth
Sunlight & Water Needs
Prefers full sun (minimum 6-8 hours); high water requirement during summer heat; becomes dormant during severe drought; prefers well-drained fertile soil with pH 6.0-7.5.
Mowing & Maintenance
Recommened height 2.5 to 3.5 inches; weekly mowing frequency; requires 2-4 lbs N per 1000 sq ft annually; high maintenance level including regular aeration.
Special Characteristics
Excellent traffic tolerance and recovery; susceptible to Dollar Spot, Necrotic Ring Spot (visible in image patches), and Summer Patch; moderate shade tolerance.
Ecological Information
Introduced/Naturalized in North America; provides soil stabilization via dense sod; often mixed with Perennial Ryegrass or Fine Fescue for biodiversity and disease resistance.