Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, subfamily Pooideae, tribe Poeae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common or 'Midnight' type (unspecified variety in image)
Hardiness Zones
USDA Zones 2-7; excellent cold tolerance, enters dormancy during extreme heat or prolonged drought.
About This Grass
A dark green, medium-textured turfgrass that forms a thick mat. It is highly valued for its recuperative ability due to rhizomes and its attractive, lush appearance. Seed heads are open panicles, often pyramidal in shape.
Blade Characteristics
Bades are 2-4mm wide (medium), flat or slightly V-shaped, with a distinctive boat-shaped (keeled) tip. Vernation is folded in the bud; ligule is short and membranous; auricles are absent. Leaves have two translucent 'mid-lines' parallel to the mid-vein.
Root System
Moderate depth (typically 6-12 inches), fibrous with extensive rhizomes. Forms heavy thatch if not managed, but provides excellent sod strength and wear recovery.
Growing Information
Origin Region
Native to Europe, Northern Asia, and the mountains of Morocco and Algeria; widely adapted to temperate climates
Growth Habit
Rhizomatous (spreading via underground stems), forming a dense, uniform sod
Sunlight & Water Needs
Full sun preferred (6+ hours), moderate shade tolerance. High water requirements; requires supplemental irrigation during summer dormancy to maintain green color.
Mowing & Maintenance
Ideal height: 2.5-3.5 inches. High maintenance level requiring regular fertilization (2-4 lbs N/1000 sq ft/year) and periodic dethatching.
Special Characteristics
Excellent traffic tolerance and recovery. Susceptible to Leaf Spot, Melting Out, and Summer Patch. Highly aesthetically pleasing for home lawns and sports fields.
Ecological Information
Introduced and naturalized in North America. Provides cover for small mammals; often blended with Perennial Ryegrass or Fine Fescue for genetic diversity and disease resistance.