This is the Right Way to Water Your Lawn
Don't be the neighbor who keeps his sprinklers going All. Night. Long.
In most Southern neighborhoods it is hard to find a home without a lawn. It serves as the foundation for the entire garden, providing a comfortable setting for enjoying the surrounding trees, shrubs, and flowers. Because of the varying climates in the South, from humid, low coastal areas to cooler, mountainous regions, there is a wide variety of lawn grasses. Warm-season grasses do well when temperatures soar above 90 degrees and include Bermuda, centipede grass, and St. Augustine. Cool-season grasses, which thrive when day-time temps are in the 70s and 80s, include Kentucky bluegrass, tall fescue, and perennial ryegrass. Each type of grass has specific needs regarding amount of sunlight and shade, but they all require appropriate amounts of water. Whether you are dealing with a drought-tolerant Bermuda or an almost-blue Kentucky bluegrass, it's important that you water it properly, whether you use a soaker hose or inground sprinklers. If you overwater, you are inviting diseases and rot. If you don't water enough, the grass roots will not grow as deep as they should, setting your lawn up for trouble when hot weather hits.
The Best Time to Water Grass
Regardless of the type of grass you are growing, the best time to water your lawn is very early in the morning before it gets hot. Most of the water will have time to soak down to the roots and the grass blades will dry quickly, preventing disease problems. Watering in the early morning hours also keeps the lawn cooler during the hottest part of the day, which means less stress on the grass. If you can't make it out first thing in the morning, late afternoon between 4-6pm is the next best time for watering. Just don't water at night; a lawn that stays wet all night long is the perfect breeding ground for growing fungus. Keep in mind that you don't always have to water your lawn. Lawns are resilient; healthy, properly cared-for lawns can survive weeks without water by going dormant (when the lawn turns brown), then recover once the rain returns.
How Long To Water Grass
A lot of homeowners are under the impression that you need to water the grass for 15 minutes every single day. Wrong. When watering an established lawn, it's normally recommended that you water until the top 6 to 8 inches of soil is wet. Most lawns need 1 to 1.5 inches of water per week—either from rain or watering—to soak the soil that deeply. You can either apply that amount of water during a single watering or divided into two waterings during the week.
How To Tell When There is Plenty of Water
Take a screwdriver and measuring tape and, using nail polish or paint, mark the 6-inch spot on the screwdriver. To see how long it will take to soak the soil, poke the screwdriver into the soil every 15 minutes to test how deep the water has moved. Mark the time once the soil has been soaked to the 6-inch mark—that's how long you'll need to water your lawn each time going forward. If you want to know whether or not you need to water, use this little tip: If you can't easily stick that screwdriver 6 inches into the soil, you need to water.
In general, warm-season grasses require less water than cool-season grasses. Your region determines how frequently you need to water because of differences in rainfall and summer weather conditions. Grass requires the most water in conditions of heat, drought, low humidity, and high winds. The type of soil you have also plays a part: Clay soil holds water longer and can be watered less frequently than sandy soil, which drains very quickly (and therefore needs to be watered more often).
When to Stop Watering in the Fall
Continue to water your lawn as needed until the ground is frozen. You don't need to water if your area receives one inch or more of precipitation each week. Just as in warmer weather, fungal diseases can take hold if your lawn is overwatered.