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 Commercial Mix (likely containing cultivars like 'Midnight' or 'Baron')
Hardiness Zones
USDA Zones 2-7; excellent cold tolerance; poor heat tolerance (struggles in Deep South); goes dormant in winter/extreme summer heat.
About This Grass
A dense, low-growing turf grass known for its dark green to blue-green color. It maintains a medium-fine texture and forms a thick carpet. Seed heads are open panicles, often pyramidal in shape, usually seen in spring.
Blade Characteristics
Narrow to medium (2-4mm); V-shaped or flat; distinctive boat-shaped (keeled) tip; dark green; folded vernation; membranous ligule; no auricles.
Root System
Moderately shallow fibrous root system with extensive horizontal rhizomes; forms thick thatch; medium establishment speed from seed; excellent sod-forming capability.
Growing Information
Origin Region
Native to Europe and Northern Asia; widely naturalized in North America and temperate regions
Growth Habit
Rhizomatous (spreading via underground stems), forming a dense, self-repairing sod
Sunlight & Water Needs
Full sun preferred (6+ hours); moderate shade tolerance; high water needs (1-1.5 inches per week); enters dormancy during extreme drought; prefers slightly acidic to neutral soil (pH 6.0-7.0).
Mowing & Maintenance
Ideal height 2.5 to 3.5 inches; weekly frequency; requires 3-5 lbs Nitrogen per 1000 sq ft per year; high maintenance level requiring periodic dethatching and aeration.
Special Characteristics
Excellent wear tolerance and recovery due to rhizomes; susceptible to Leaf Spot, Dollar Spot, and Summer Patch; moderate salt tolerance; high aesthetic quality for home lawns.
Ecological Information
Introduced/Naturalized in US; provides cover for small mammals; stabilizes soil effectively through dense sod; often mixed with Perennial Ryegrass or Fine Fescue for diversity.