By Brad Haire
University of Georgia
It doesn't matter if you use a sprinkler attached to a hose or a permanent system. The first thing you need to know is how much water you are applying and how fast, said Kerry Harrison, an irrigation specialist with the University of Georgia Extension Service.
"Not knowing your water application rate is like driving a car with no speedometer," he said.
Gauge systemDifferent systems apply water at different rates, he said. Hose- sprinkler systems vary the most. Space three rain gauges within the watering area of your system. Look at your watch. After an hour has passed, check your gauges to see how much water your system puts out in that time.
Most lawns grow best when they get one inch of water a week, either from rain, irrigation or combination of the two. And they prefer long soakings. In dry weather, water only once or twice a week to get that one inch of water. This promotes deeper roots. Deep roots mean better looking, healthier lawns.
Light, frequent watering can actually lead to diseases and hurt your lawn, he said.
The grass at the very end of a sprinkler's trajectory may not get as much water as the grass closer to the sprinkler. Permanent systems should be set for overlap in sprinkler patterns to adjust for this. Remember this when you move your hose-sprinkler system. You want your lawn to be uniformly wet.
Right timeYou need to water at the right times, too. Or you could just waste time and water. Water in early morning or late at night, Harrison said.
"We have research and evidence to show that you can lose as much as half the water if it's applied during peak daylight hours," he said.
High temperatures and high winds can evaporate water or blow it off target, too, he said.
Most watering restrictions allow watering at the right times.
Also, watering during the day increases the time grass is wet. This can lead to disease problems. Watering at night won't hurt grass that's already wet from dew. The turf gets the water it wants and is drier during the day.
There are no special watering restrictions now in Georgia. The state is in a mild drought, though, said state climatologist David Stooksbury, a professor of engineering with the UGA College of Agricultural and Environmental Sciences.
An unusually dry period from October 2003 through March 2004 has led to dry soils and low stream flows across the state.
(Brad Haire is the former news editor with the University of Georgia College of Agricultural and Environmental Sciences.)