Watering
Lawns with shallow roots depend on frequent watering
watering frequency Many people in Florida have made the mistake of developing a shallow, weak root system in their lawn by watering too frequently for short periods of time. When a timer is used to water a lawn and it is set to come on frequently for short periods of time (every day for 20 minutes for example), the result will be a shallow root system and a lawn that will become dependent on its shallow roots being watered frequently.
To develop a deep root system and a lawn that will go through hot, dry weather in better shape without requiring water as often, it may be necessary to switch the automatic timer to manual.
Watering a lawn on an as-needed basis is the best way to water correctly and develop a deep-rooted lawn.
There are several clues to a lawn's need for water. When the grass is in need of water, footprints will remain long after being made. In other words, you can walk across the lawn, turn around and see your tracks.
grass with folded blades Another sign of water need is leaf blades that fold in half along the midrib, like a book closing.
A color change in the lawn is also an indication of moisture stress. If bluish-gray areas appear in the grass, water is needed. Finally, if a soil sample taken from the root zone feels dry, water is needed.
When 30 to 50 percent of the lawn shows these signs of water need, it is time to irrigate. The lawn will fully recover within 24 hours. The lawn should not be watered again until it shows the signs of wilting described.
Watering frequency and volume are interrelated. A general rule for Florida lawns is to supply from empty cans one-half to three-quarter inch of water per application. This is about 300 to 600 gallons for each thousand square feet of grass. You can easily determine how long it takes to apply this amount of water by placing empty cans (coffee, soup, tuna, etc.) in the spray pattern, turn the sprinklers on and time the length of water application. For example, if you let the water run for 30 minutes and collect an average of one quarter inch water in the cans, you then know you'll have to let the sprinklers run for one hour to apply one half inch water.
Once you've determined the proper frequency and correct amount, you must decide when to water. While it's true that watering during the hottest part of the day will beneficially cool the grass, this practice wastes water which is rapidly lost through evaporation. Based on current research, watering a lawn when the grass is already wet from dew does not create disease problems. However, watering to extend this period of natural wetness (when the grass is wet from dew), can provide the right conditions for lawn disease development. For example, if you water at dusk before the dew falls or late morning as the dew is drying you are extending the time the grass stays wet. Most lawn diseases need this extended period of wetness to infect your grass. If you want to pick the ideal time to irrigate, it would be during the early morning hours (about 4 to 8).
The irrigation schedule described in this article works for any type of soil or lawn grass and will promote a lawn that requires less mowing and has little thatch buildup. Proper watering will also help develop a deep root system and encourage a lawn that is less susceptible to damage by pests and environmental stresses.
