Kentucky Bluegrass
Poa pratensis · Cool-season (C3), Perennial
Grass Family
Poaceae, Subfamily Pooideae, Tribe Poeae
Grass Category
Lawn/Turf Grass
Variety / Cultivar
Likely a common turf-type blend (e.g., 'Midnight' or 'Baron' lineage)
Hardiness Zones
USDA Zones 2-7; exceptional cold tolerance; poor heat tolerance in deep South; enters winter dormancy.
About This Grass
Medium-to-fine texture with a distinctive dark green to blue-green color. Grows 6–12 inches if unmowed; forms a plush, carpet-like mat when maintained. Seed heads are open, airy panicles shaped like pyramids.
Blade Characteristics
Fine to medium width (2-4mm); V-shaped or flat; boat-shaped (keeled) tips; dark green color; folded vernation; very short membranous ligule; no auricles.
Root System
Shallow to moderate depth; highly rhizomatous; produces significant thatch; slow to establish from seed but creates a very stable sod with excellent recovery via rhizomes.
Growing Information
Origin Region
Europe, Northern Asia, and Northern Africa; well-adapted to the Northern United States and Canada
Growth Habit
Rhizomatous (spreading via underground runners), forming a dense, self-repairing sod
Sunlight & Water Needs
Full sun preferred (minimum 6 hours); moderate to high water needs; goes dormant (browns) during severe drought to protect the crown; prefers well-drained soil with pH 6.0–7.5.
Mowing & Maintenance
Ideal height 2.0–3.5 inches; frequent mowing required during peak spring/fall growth; 2–4 lbs Nitrogen per 1000 sq ft annually; requires periodic dethatching; high maintenance level.
Special Characteristics
Excellent wear tolerance and recovery; high aesthetic value; susceptible to leaf spot and dollar spot; good salt tolerance; poor shade tolerance compared to fescues.
Ecological Information
Introduced and naturalized in North America; provides forage for various insects and small mammals; excellent for erosion control on slopes due to rhizome network; often blended with Perennial Ryegrass or Fine Fescue.