Comparing turfgrass is the first step to growing a gorgeous lawn. Two widely planted grass species are bermudagrass (Cynodon dactylon) and Kentucky bluegrass (Poa pratensis). Despite their popularity, they differ greatly. Choose the right turfgrass for your yard by determining which one best fits the site's conditions and your lifestyle. Your lawn grass should be able to thrive in its environment while withstanding your pet's and family's day-to-day use of it.
Bermudagrass is generally a warm-weather species and suited for drought-prone regions. Only a few hardy strains of bermudagrass tolerate the often subzero temperatures of U.S. Department of Agriculture plant hardiness zones 5 through 6. Restrict its use to USDA zones 7 through 10.
Kentucky bluegrass, however, is hardy in USDA zones 2 through 7; in USDA zone 2, the average annual extreme low temperature is minus 45 to 50 degrees Fahrenheit. Kentucky bluegrass grows during periods of drought, but it's less drought-tolerant than bermudagrass.
Texture, Appearance and Resilience
Bermudagrass' medium-course, wiry texture makes it resilient and effective in high-foot-traffic areas. Each of its blades or leaves is smooth and pointed with white hairs that form a noticeable ring where the blade meets a papery leaf sheath. The species grass is typically gray-green, and some hybrid varieties are a deep blue-green or dark green.
Kentucky bluegrass can recuperate quickly from wear, making it an option for all-purpose lawns. Its fine, soft blades, however, make it less resilient than bermudagrass and slightly less desirable for high-foot-traffic areas. It is characterized by smooth, compressed sheaths. Each blade has a boat-shaped tip, making Kentucky bluegrass less spiky and more comfortable underneath bare feet than bermudagrass. Its blades and sheaths are dark green.
Bermudagrass is generally used as a forage grass due to its ability to creep and grow rapidly. It is also considered an invasive weed. Prevent bermudagrass from becoming invasive by:
- Continually removing it so that it won't produce new seeds or stems.
- Allowing unwanted areas of bermudagrass to dry out by withholding watering then spading or tilling those areas.
- Increasing shade over areas that you don't want it to invade.
- Covering the grass with black plastic and black polyethylene mulch.
Bermudagrass can range from low to high maintenance, depending on the quality of lawn you want to achieve. Its fast-growing, leafy, branched stems can grow 4 to 6 inches tall, and under the most ideal conditions up to 18 inches tall. Frequent, low mowing, along with watering, results in the highest quality bermudagrass turf. Less watering results in good or fair turf and a reduction in how often it needs to be mowed.
Kentucky bluegrass requires more maintenance than bermudagrass. Its shallow root system requires more frequent watering during warm weather. Summer months without sufficient rainfall or irrigation can cause it to become dormant. It can be mowed short -- down to 1 1/2 inches -- during cool months and allowed to grow 3 to 4 inches tall during summer.
Pest and Disease Susceptibility
Bermudagrass generally has few pest issues, according to the Alabama Cooperative Extension System. Common pests that feed on bermudagrass include:
- Armyworms, which range from light green or tan to dark green or brown and have spots that form long lines down the body lengths. They are 1 1/2- to 2-inch-long worms that cause brown spots on the grass.
- Bermudagrass mites, which are microscopic, wormlike, four-legged creatures that feed on sap.
- Rhodegrass scale, or mealybugs, are tiny, light-colored or white scale insects that also feed on sap.
Pests and diseases typical of Kentucky bluegrass include:
- White grubs, which have grayish-white bodies and brown heads and can grow 3/8 inch to 2 inches long.
- Billbugs, which look like white grubs but have no legs and grow 1/4 to 1/2 inch long.
- Powdery mildew, a fungal disease that causes spots and white patches.
- Yardcare.com: Cool-Season Grasses
- U.S. Department of Agriculture: Planting Guide -- Bermudagrass
- University of California Integrated Pest Management: Bermudagrass
- Lawn Care Academy: Kentucky Bluegrass -- America's Favorite Cool-Season Grass
- Texas A&M AgriLife Extension, Richard Duble: Bermudagrass -- The Sports Turf of the South
- Texas A&M AgriLife Extension, Richard Duble: Kentucky Bluegrass