Turfgrass by Karla Basallaje, Master Gardener.
Because it serves so many purposes and provides many benefits, it is easy to forget that turfgrass is likely the largest plant in your garden. Not only does it provide your home with curb-appeal, it controls soil erosion and runoff; it limits dust and noise, as well as helping to dissipate heat. As with other plants in your garden, they need care; more specifically, your lawn needs to be mowed, watered and fed.
Ideally, it would make sense to start with a soil test, so that a better understanding of what nutrients your soil needs to support the plants growing in it can be determined. Mowing is a crucial step in maintaining a healthy lawn. Experts recommend mowing no more than a third of the grass blade. Keep your mower blades sharp so that the grass blade is cut and not torn. The height of the grass blade affects how much chlorophyll the grass has available for photosynthesis. The more green tissue is available, the more carbohydrates are produced and stored, especially in the spring and summer, which is growing season for warm season grasses. Conversely, the shorter the blade, the weaker and more stressed your turf becomes as carbohydrate production and storage is reduced, leaving your lawn vulnerable to insect attacks, disease, and weed spread due to the lack of reserves. Don’t bag your clippings; mulch them into the lawn to reduce water use, to help choke out weeds and help put nitrogen back into the soil.
The first step to evaluating your watering needs is to make sure your irrigation system is in good working order – look for broken or leaking sprinkler heads. Do not water sidewalks or driveways. Don’t over-water your lawn. Never water your turf to the point of run-off. It is preferable to irrigate more deeply to encourage root growth, which will withstand dry weather better. The general recommendation is to water about one inch of water per week. There are, however, mitigating factors to consider including soil type and weather. The best time to water is in the morning as opposed to the evening to avoid moisture clinging to your lawn throughout the night making it susceptible to disease. Visit texaset.tamu.edu for assistance in calculating sprinkler run times.
The time to start fertilizing your lawn is sometime in the spring as there is usually enough reserved nitrogen to see the grass through the first two or three mowings. Examine your lawn and if growth appears vigorous, you can wait to fertilize until May. In the absence of a soil test, apply fertilizer with a 3-1-2 nitrogen, phosphorus, potassium (N-P-K) ratio (example: 15-5-10) or a 2-1-1 ratio (example: 15-5-10). Continue to observe your lawn and apply fertilizer every 6-8 weeks or so during the growing season depending on the turf and type of fertilizer.
With proper and diligent care, many turf problems may be averted. Most insect problems take place in full sun, while most disease problems take place in the shade. Lawn problems usually appear as brown or yellowing spots and can range from drought stress to brown patch to chinch bugs.
For help in determining lawn problems see the helpful earth-wise guide and flow chart at aggie-horticulture.tamu.edu