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Pinellas County Cooperative Extension ServiceBeautiful blades don't always come easily. But they are possible with proper care and nourishment.
Our landscape is like a room outside our home, so we want to keep it looking great. But that can be a challenge, especially with conventional irrigation systems. The most efficient way to water a lawn is when the grass begins to show signs of stress. For example:
When the lawn has bluish-gray areas.
When footprints or tire tracks remain long after being made.
When many leaf blades folded in half.
When soil samples from the root zone feel dry.
Prolonged hot, dry periods, strong wind and low relative humidity can also cause signs of stress. During such times, plants wilt even though water may be in the soil; that's because they are losing water faster than it can be absorbed through the root system.
Through careful planning, homeowners can use their water responsibly and still grow a lawn that will survive on little or no supplemental irrigation.
A prepared lawn can withstand more stress than a lawn that is not conditioned because of its deep root system and leaves that are toughened through proper management practices.
Proper irrigation is the first step in conditioning a lawn for drought. Daily light watering causes shallow root systems that are not good for healthy turf. To develop a deep root system, lawns should be watered only when the first signs of wilt occur.
Apply just enough water to wet the soil in the root zone. For Florida's sandy soil, three-quarters of an inch of water is sufficient. The next irrigation should be withheld until signs of wilt occur again. This technique works regardless of turf grass species, soil type, season and other environmental conditions.
It may take up to six weeks to condition a turf to survive a week or more without wilting between irrigations or rainfall. During this time, the root system is developing and growing deeper. Stolons (above-ground stems) that are not rooted will die. In time, the lawn will establish a more uniform appearance with less thatch and deeper grass plant.
Know when to mow
Proper mowing practices are essential for drought-prepared turf. Every time a lawn is mowed, the metabolism of the grass plant is stressed, which reduces root growth. Mowing frequency and cutting height must be considered for a healthy lawn.
Use the highest setting on the mower for conditioning the turf, because a low cutting height will stress the turf. By increasing the grass leaf area, more photosynthesis can occur. This results in more carbohydrates for plant growth, especially root growth. The higher the cut of a lawn (up to 4 inches), the deeper the root system will become.
Although transpiration (water loss through leaves) will be slightly greater with higher-mowed turf, the expanded root system will be more advantageous.
Mowing, however, should be done often enough to minimize the shock of cutting. Never remove more than one-third the height of the lawn at a time. If the lawn is allowed to grow to 4 inches, do not mow it lower than 3 inches. Adjust the frequency of mowing to the growth of the turf.
In the summer, it may be necessary to mow several times a week, but in the winter, once a month may be enough.
Keeping the mower blades sharp and properly balanced is also an important part of mowing. A leaf blade cut by a sharp blade will recover more quickly and lose less water than a leaf blade shredded by a dull blade.
Fertile ground
Fertilization can enhance the drought tolerance of turf grasses, but it must be done properly and with the knowledge of how nitrogen and potassium affect grass plants.
No matter how much you boost drought conditioning through proper irrigation and mowing practices, the process can be undermined by excessive nitrogen fertilization. Shoot growth is enhanced and root growth reduced by excessive nitrogen. Leaf blades become more lush as nitrogen fertilization increases.
Drought conditioning can be accomplished only by applying just enough nitrogen to obtain a small but continuous amount of growth. Lawns should never be fertilized to deepen the color, because Southern turf grasses, except Bermudagrass, are more yellow-green.
Potassium fertilization can help turf grasses increase their tolerance of stress. Potassium promotes increased root growth and thicker cell walls. Turf grasses require potassium in nearly the same amount as nitrogen, especially in sandy soils where both can easily leach out.
Other macro and micro nutrients, as well as the soil pH, should be kept at recommended levels for optimal growth. An occasional soil test is helpful in monitoring pH levels.
Clip this
To remove or not remove lawn clippings?
This is a question we hear almost daily. Contrary to popular belief, clippings do not contribute to the thatch layer. The stems, rhizomes and stolons of grass produce thatch. On most lawns, clippings should be allowed to filter through the grass and recycle nutrients to the soil. If your lawn is mowed often, clippings cause few problems. Clippings should be removed only if large amounts accumulate on top of the grass.
Spread the seed
The best time to seed Bahiagrass is from April to September. Bahiagrass seed is large and requires 5 to 10 pounds to cover 1,000 square feet.
The lawn should be moist and level. The seed will need to be covered or raked into the soil to a depth of 1/4 to 1/2 inch. Keep moist until germination occurs, which may be three weeks or more. If the soil is allowed to dry any time after the seeds have started to swell, many of them will die.
- Compiled by Opal W. Schallmo and Nancy R. Volmar of the Pinellas County Cooperative Extension Service. If you have questions, call them at (727) 582-2100.