Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, subfamily Pooideae, tribe Poeae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Common/Naturalized Kentucky Bluegrass (non-specified cultivar)
Hardiness Zones
USDA Hardiness Zones 2 through 7; excellent cold tolerance, poor heat tolerance compared to warm-season grasses.
About This Grass
A dark green, medium-textured turfgrass that forms a thick sod. It is known for its relatively slow establishment from seed but excellent self-repair capabilities. It reaches a height of 12-24 inches if left unmowed, featuring a panicle seed head.
Blade Characteristics
Narrow blades (2-4mm), V-shaped or flat, featuring a distinct boat-shaped tip. Vernation is folded in the bud. Ligule is short and membranous; auricles are absent.
Root System
Relatively shallow to moderate fibrous root system supported by vigorous rhizomes. Low to moderate thatch tendency; excellent sod-forming capability and wear recovery.
Growing Information
Origin Region
Native to Europe, Northern Asia, and the mountains of Morocco and Algeria; widely adapted to temperate climates globally.
Growth Habit
Rhizomatous (spreading via underground stems), forming a dense, uniform sod over time.
Sunlight & Water Needs
Prefers full sun (minimum 6 hours) but tolerates light shade. High water requirements; enters summer dormancy during severe drought to survive. Prefers well-drained soil with pH 6.0-7.5.
Mowing & Maintenance
Recommended height: 2.0-3.5 inches. Requires moderate to high maintenance including 2-4 lbs Nitrogen/1000 sq ft annually and periodic core aeration.
Special Characteristics
Excellent wear tolerance and recovery due to rhizomes; highly susceptible to leaf spot, melting out, and necrotic ring spot in humid conditions.
Ecological Information
Introduced and naturalized in North America. Widely used for soil stabilization and erosion control. Often blended with Perennial Ryegrass or Fine Fescue for improved genetic diversity.