Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
AI-generated identification · may be incorrect
Grass Category
Lawn/Turf Grass
Hardiness Zones
USDA Hardiness Zones 3 to 7, exhibits excellent cold tolerance, goes dormant and turns brown during extreme summer heat or winter freezes.
Grass Family
Poaceae, subfamily Pooideae
Variety / Cultivar
Midnight (known for dark blue-green color and aggressive rhizome spread)
About This Grass
A classic fine-to-medium textured turfgrass with a rich dark green to blue-green color. Forms a dense, wear-resistant carpet. When unmanaged, can grow up to 18-24 inches with pyramidal seed heads, but maintained turf is kept short at 1.5-2.5 inches.
Blade Characteristics
Medium-fine width (2-3mm), flat to V-shaped blades with characteristic boat-shaped tips. Vernation is folded in the bud. Prominent parallel veins with a light-colored midrib. Ligule is short and membranous, auricles absent.
Root System
Moderately deep fibrous root system combined with vigorous rhizomes. Establishes relatively slowly from seed but creates an extremely tough, dense sod. Moderate thatch-forming tendency.
Growing Information
Origin Region
Europe, Northern Asia, and parts of North America; cultivated widely in temperate regions worldwide
Growth Habit
Rhizomatous, forming a dense, uniform turf via underground creeping stems
Sunlight & Water Needs
Requires full sun (at least 6-8 hours daily), moderate to high water needs to maintain green color during summer, enters dormancy under severe drought with good recovery capability. Prefers well-drained loamy soils with a pH of 6.0 to 7.0.
Mowing & Maintenance
Ideal mowing height is 2.0 to 3.0 inches. Regular mowing frequency needed during spring and fall growing peaks. High fertilizer requirement (3-4 lbs N per 1000 sq ft annually). High overall maintenance level.
Special Characteristics
Exceptional wear and traffic tolerance due to aggressive rhizomatous recovery. Good cold tolerance. Moderate shade tolerance compared to fine fescues. Susceptible to certain diseases like dollar spot and leaf spot under high humidity.
Ecological Information
Introduced species in North America widely used for erosion control on slopes, sports fields, and residential lawns. Provides moderate wildlife value for grazing animals and ground-nesting birds. Often mixed with perennial ryegrass and fine fescues.