Kentucky bluegrass is the best known and most widespread of all cool season grasses. In the northern regions of the United States Kentucky bluegrass is used extensively on home lawns, parks and sports fields. Requiring lots of sunlight, water and fertilizer, Kentucky bluegrass creates a dense, high-quality lawn that is tolerant of foot-traffic. Kentucky bluegrass varieties have unique adaptations for specific lawn environments including usual heat and disease tolerances.
According to Rutgers University, Compact-America bluegrass forms a dense turf with fine-textured leaf blades that retain their color throughout moderate winter temperatures. Sensitive to hot summer temperatures like common bluegrass, the Compact-America variety exhibits a faster-than-average recovery from this heat-induced dormancy. This variety of bluegrass is resistant to powdery mildew and leaf spot fungal diseases.
Thermal blue is a bluegrass variety that grows well in warm summer temperatures and in moderately shady environments. This unusual adaptation to warm temperatures allows thermal blue to grow in transitional climates as far south as South Carolina. Thermal blue's heat-resistance has not diminished the density and aesthetic appeal of the turf, as it retains the look and feel of common bluegrass.
Rough bluegrass has yellow-green leaves with a soft, glossy texture and is well adapted to moist, cool environments. This variety is tolerant of shade and cold temperatures but lacks tolerance to warm temperatures, heavy usage and drought. Rough bluegrass is sometimes considered as grassy-weed and can out-compete other more desired bluegrass varieties.
Mid-Atlantic bluegrass is a fast-growing, high-density turf grass with a deep root system that enables good resistance to drought and disease. This bluegrass variety has better-than-average tolerance to warm and cold temperatures and exhibits faster-than-normal recovery from temperature-induced stress. Highly susceptible to leaf spot fungal disease, mid-Atlantic bluegrass is usually able to self-recover from such infections due to the extensive root system.