Turfgrasses are divided into two categories based on their climate adaptation. Cool-season grasses grow best in the spring and fall, with optimum growth when the temperature is between 60 and 75 degrees Fahrenheit. Warm-season grasses grow best in the summer, with optimum growth at 80-90 degrees Fahrenheit. Delaware is in the transition zone. Our winters are too cold for warm-season grasses and our summers are too hot for cool-season grasses. Since we are in the northern part of the transition zone, we struggle with the following list of cool-season grasses.
Kentucky Bluegrass – This high-quality turf has a nice green color and good recuperative ability. But, it damages easily, suffers from heat and drought, requires moderately high maintenance, has a tendency to thatch, is susceptible to many diseases, and is intolerant of shade or salt.
Perennial Ryegrass – This turfgrass establishes very rapidly and is often included in grass mixtures to provide a quick cover. It does not wear or recuperate well and is intolerant of heat, drought, shade, and salt. Perennial ryegrass is susceptible to a moderate number of fungal diseases.
Tall Fescue – The new turf-type tall fescues are excellent for Delaware. While they take a little while to establish or recuperate since they are a clump-type grass, they are extremely wear resistant; drought-, heat- and salt-tolerant; and moderately shade tolerant. Tall fescues have few disease problems and require less maintenance that other grasses. Kentucky bluegrass is the first grass to brown out in the summer and tall fescue is the last.
Fine-leaf Fescues – Fine fescues have an extremely narrow, almost needle-like leaf blade. They are included in turfgrass mixtures for their excellent shade tolerance. Fine-leaf fescue often appears in neglected lawns because it withstands a high pH. Due to its fine texture, fine-leaf fescue is often difficult to mow.
Bentgrass – This fine-textured grass is unique among cool-season grasses in its ability to be cut at heights of 1/2 inch or less. It has a high disease potential, poor drought tolerance and requires extremely high levels of maintenance. Bentgrass is a weed in home lawns and should be left on the golf course where it belongs.
Zoysiagrass – This is the only warm-season grass grown as a lawn in Delaware. Zoysia is easy to identify because its leaves are covered with stiff hairs. It remains brown well into the spring and turns brown again with the first fall frost. Zoysia is very invasive and is often a bone of contention between neighbors. The most logical place for zoysiagrass is at a beach residence where it is viewed only during the summer.
Since no one grass has a full list of desirable characteristics, we use blends of cultivars and mixtures of species to achieve versatile lawns with fewer shortcomings (with the exception of tall fescue and zoysiagrass).
This following lists of cultivars are recommended based on results from the National Turfgrass Evaluation Program. These cultivars scored high in the most recent evaluations at test locations in College Park, Maryland with conditions that are similar to Delaware. Some of the cultivars are new and may not be readily available in the trade.
|Solar Eclipse||Nu Destiny||Ginney II||Bluestone||Blue Note||Diva||Shamrock|
|Octane||Palmer V||Rio Vista||Sox Fan||Uno||Mach I|
|Pizzazz 2 GLR||Sideways||Allante||Fiesta 4||Insight||Dominator|
Tall Fescue (recommended – 90-100% on a wight basis):
|Spyder||Catalyst||Toccoa||3rdMillenium SRP||Pedigree||Falcon IV|
|Faith||Falcon V||Turbo||Falcon NG||Traverse SRP||Stetson II|
|Umbrella||Firecracker LS||Bullseye||Finelawn Xpress||Tulsa Time||Tahoe II|
|Cannavaro||Shenandoah Elite||Shenandoah III||Van Gogh||Mustang 4||Darlington|
|Braveheart||Speedway||Wolfpack II||Justice||Rhambler SRP||Escalade|
|Gotham||Beacon||Longfellow 3||Zodiac||Treazure II|
|Spartan II||Bighorn GT||Wrigley 2||Intrigue||Cascade|
Zoysia (Varietal differences in texture and winter hardiness are important considerations):
Endophytic cultivars have within the seed and plant itself a beneficial fungus called an endophyte. The fungus is unable to live outside the seed or plant, and so depends upon the plant for its survival. The plant also benefits from its association with the fungus. Endophyte enhanced cultivars tend to be vigorous even under conditions of stress, such as minimal fertilization and irrigation, and exhibit a level of resistance to foliar -eeding insects such as chinch bugs, billbugs, and sod webworms.