Turfgrass Management in Oklahoma
Turfgrass serves a vital role in the landscape. It reduces wind and water erosion, provides a place for outdoor recreation and increases the value of residential property. Maintaining a healthy turfgrass yard requires planning and proper upkeep.
Start by selecting a grass well adapted to Oklahoma’s variable temperature and moisture, site conditions, and your personal need. The table below provides sun requirements, heat tolerance and irrigation requirements of particular turfgrasses.
|Turfgrass||State||Sun Requirements||Drought Resistance||Heat Tolerance||Irrigation Requirements|
|Warm Season Turfgrass|
|Bermudagrass||Statewide (May be susceptible to winter kill in Northern areas)||Full Sun||Excellent||Excellent||Low|
|Buffalo grass||Central and Western||Full Sun||Excellent||Excellent||Low|
|St. Augustinegrass||Southern along the Red River||Full sun to shade||Good||Excellent||Medium|
|Zoysiagrass||Central and Eastern||Full sun to light shade||Very Good||Excellent||Medium|
|Cool Season Turfgrass|
|Kentucky Bluegrass||Northern and Eastern||Full sun to shade*||Good||Fair||High|
|Perennial Ryegrass||Northern and Eastern||Full sun to shade*||Poor||Fair||High|
|Tall Fescue||Statewide||Full sun to shade*||Good||Good||High|
*Recommended for lightly shaded areas in Oklahoma, requires more maintenance and irrigation in full sun.
Avoid watering frequently and lightly which causes shallow rooting, thatch accumulation and weed germination. Turf should be watered when needed and not on a regular schedule. The amount of water your turfgrass needs is influenced by soil texture and changes in weather.
Only water turfgrass when it shows the first signs of wilt (leaves will begin to roll or fold and turn blue or gray). Most turfgrasses in Oklahoma can survive with no watering in the spring or fall, except in extended drought periods. During the summer months, enough water should be applied to wet the soil to a 6-inch depth (approximately 1 to 2 inches per week). If water begins to puddle or runoff, turn the system off and allow water to soak into the soil. Repeat this cycle until the proper amount of water is applied.
Setting the mowing height to 2 to 3 inches for warm season grass and 3 to 4 inches for cool-season grass during the summer will help conserve soil moisture. Grass acts as a natural mulch, retaining soil moisture and shading out weeds. Mow as needed to remove no more than 1/3 of the leaf material per mowing to prevent scalping.
Instead of bagging grass clippings, use a mulching lawn mower or spread the clippings around the yard. Bagging grass clippings removes valuable nutrients from the lawn and take up space in the landfill.
Aerate the Lawn
Aerating is the process of taking small plugs out of the ground or forcing tines into the soil to reduce soil compaction. In high traffic areas, soil can become compact which prevents air flow, water infiltration, and nutrient intake. Aeration will benefit turfgrass by increasing the effectiveness of irrigation and fertilization. Different types of aerating machines can be rented or purchased from local stores.
Thatch is dead, un-decomposed roots and stems that is caused when plant tissue production exceeds decomposition. Excessive thatch layers can reduce water, air and nutrient movement into the root-zone of the soil. This can lead to shallow root development.
The thickness of the thatch layer can be determined by observing a 3- to 4- inch plug. If the thatch is thicker than 0.5 inch, the yard would benefit from dethatching. Dethatch warm-season grasses like bermudagrass and zoysiagrass before the grass greens up in the spring. Use a dethatching machine or a power rake to reduce the thatch layer. For small lawns use a thatch rake to reduce thatch layers.
How to prevent thatch
Only fertilize as needed. Apply 2 to 3 lbs of N per 1,000 sq. ft. for cool-season and 3 to 4 lbs of N per 1,000 sq. ft. for warm-season depending on use and site conditions. For all turf types, apply P and K according to soil test results. Water deeply but infrequently to encourage deep root growth