Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3
Grass Family
Poaceae, Subfamily Pooideae, Tribe Poeae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common-type mixture (likely including older cultivars based on blade width and growth pattern)
Hardiness Zones
USDA Zones 2-7; excellent cold tolerance; poor performance in the deep South due to heat stress; goes dormant in winter.
About This Grass
Medium-textured turf grass with a distinct dark green to blue-green color. It forms a dense mat and is highly valued for its aesthetics and recuperative ability. Seed heads are open, pyramidal panicles if left unmowed.
Blade Characteristics
Blade width 2-4mm (medium); flat or slightly V-shaped; distinctive boat-shaped (keeled) tip; midvein is prominent; vernation is folded; ligule is short and membranous; auricles are absent.
Root System
Strongly rhizomatous with a fibrous root system localized in the top 6-8 inches of soil; moderate thatch-forming tendency; slow establishment from seed but forms a very stable sod.
Growing Information
Origin Region
Europe, North Asia, and Northern Africa; widely adapted to temperate climates globally
Growth Habit
Rhizomatous (spreading via underground stems), forming a dense, self-repairing sod
Sunlight & Water Needs
Full sun preferred (6+ hours); moderate shade tolerance; requires consistent moisture (~1 inch per week); moderate drought tolerance but will enter dormancy (turn brown) during heat/drought to survive.
Mowing & Maintenance
Ideal height 2.5–3.5 inches; weekly mowing; 2-4 lbs Nitrogen per 1000 sq ft per year; periodic core aeration recommended; High maintenance level.
Special Characteristics
Excellent wear tolerance and recovery due to rhizomes; susceptible to leaf spot, melting out, and necrotic ring spot; high salt sensitivity; best overall aesthetic for northern lawns.
Ecological Information
Introduced/Naturalized in North America; provides cover for small insects; excellent soil stabilizer for erosion control; commonly blended with Perennial Ryegrass or Fine Fescue for genetic diversity.