Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, Subfamily Pooideae, Tribe Poeae
Grass Category
Lawn/Turf Grass, Sports Turf, Golf Course Grass (Fairways/Roughs)
Variety / Cultivar
Common or Elite Cultivar (e.g., 'Midnight' or 'Baron' typical for dark green lawns)
Hardiness Zones
USDA Zones 2-7; excellent cold tolerance; enters summer dormancy and winter dormancy.
About This Grass
A dense, low-growing turf grass with a characteristic dark green or blue-green color. It forms a lush, uniform mat that can go dormant in extreme heat but recovers quickly in cool weather. Seed heads are open panicles.
Blade Characteristics
Fine to medium width (2-4mm); smooth, flat or slightly folded blades; distinct 'boat-shaped' (prow-like) tip. Vernation is folded in the bud; ligule is short and membranous; auricles are absent.
Root System
Relatively shallow to moderate fibrous roots supported by extensive rhizomes. Known for thick thatch development and excellent sod-building capabilities.
Growing Information
Origin Region
Native to Europe and Northern Asia; widely adapted to temperate regions of North America and Europe.
Growth Habit
Rhizomatous (spreading via underground stems), forming a dense, self-repairing sod.
Sunlight & Water Needs
Prefers full sun (needs 6+ hours) but some cultivars tolerate light shade. High water requirements; requires regular irrigation during summer to prevent dormancy. Prefers well-drained soil with pH 6.0-7.0.
Mowing & Maintenance
Ideal mowing height is 2.5 to 3.5 inches. High maintenance level; requires 3-5 lbs of Nitrogen per 1000 sq ft annually and frequent mowing during peak spring/fall growth.
Special Characteristics
Excellent wear tolerance and recovery due to rhizomes; high aesthetic quality; prone to Necrotic Ring Spot and Summer Patch; moderate shade tolerance.
Ecological Information
Introduced and naturalized in North America. Highly effective for soil stabilization and erosion control. Often mixed with Perennial Ryegrass or Fine Fescue for genetic diversity.