Be better informed when it comes to irrigating your lawn

In recent years, much attention and controversy has surrounded the water requirement of the lawn. Misinformation and hidden agendas have fueled this controversy. However, there are some well-documented facts about the American lawn.

  • The lawn is an integral component of the landscape. The lawn is certainly the best recreational surface for children and athletes.
  • The lawn has a tremendous mitigating effect on the environment, reducing heat loads and noise, plus water and air pollution.
  • A lawn is second only to a virgin forest in the ability to harvest water and recharge groundwater resources. And as a design component, the lawn provides landscape unity and simplicity while inviting participation in the landscape.

The lawn has become a focus in reducing landscape water use because of the tremendous opportunity for abusive use of irrigation water in the name of maintaining the lawn. Within the traditional landscape, the lawn has received the major portion of the total landscape irrigation. Lawn irrigation can be reduced, while the homeowner continues to derive the many benefits of turf grass. Specific strategies to reduce lawn irrigation include:

  • Place lawn areas into landscape irrigation zones based on water requirements, so that lawns can be watered separately from other landscape plantings
  • Select adapted, lower-water demand turf species and varieties
  • Use irrigated lawn areas only in areas which provide function (i.e. recreational, aesthetic, foot traffic, dust and noise abatement, glare reduction, temperature mitigation)
  • Use non-irrigated lawn areas where appropriate
  • Irrigate properly based on the lawn’s true water needs
  • Increase mowing heights to decrease lawn water use and stress
  • Decrease fertilizer rates and properly schedule fertilizations.

By implementing these strategies, homeowners can reduce lawn irrigation requirements and still reap the many benefits of a cool, green lawn.

This article is provided by Dr. Doug Welsh of Texas Agricultural Extension Service.

Preserving Your Lawn During the Drought

Contrary to popular belief, lawns do not need frequent waterings. Some turf grasses can survive if they are watered deeply once every seven to 10 days. Lawns offer significant environmental benefits, energy savings, and aesthetic value. They cool a home at the same rate as a one-ton air conditioner, trap dust, absorb noise, and offer children and adults an outdoor living space. Here are some tips that will help you preserve your lawn during the drought:

  • Aerate and dethatch the lawn – punch holes in it with a hand or power aerator – and dethatch to remove dead grass. Spread organic matter lightly in the holes left by the aerator. The organic matter will help pull the water down into the root zone of the grass. This will encourage deep rooting, increase water penetration, and reduce runoff.
  • Water the lawn more efficiently. Schedule waterings for early morning when there is little or no wind and minimal sunlight. Water at a depth of four to six inches and in short intervals to avoid runoff. Extend the time between waterings to promote greater tolerance to dry spells.
  • Keep the lawn shape simple so the lawn will be easy to water. Avoid planting narrow strips of lawn and mixing lawn with other plants.
  • Mow higher. Let lawns grow to the maximum recommended height. Longer blades of grass need less water. Mow St. Augustine grass and buffalograss at three inches; Bermudagrass at one inch, and centipedegrass and Zosiagrass at two inches.
  • Properly fertilize your lawn. Too much nitrogen will stimulate thirsty, new growth. Apply other nutrients such as iron and potassium in proper amounts as needed to encourage deep roots. Fertilize once in spring and again in the fall. Use a slow-release form of nitrogen in spring and a quick-release form in fall. Apply one pound of actual nitrogen fertilizer per 1,000 square feet of lawn at one time.
  • Weed lawns regularly. A weed-free lawn is healthier, and weeds compete for water.
  • Upgrade or automate your sprinkler system. Old, outdated sprinkler systems waste water. Use low-volume sprinklers with matched-precipitation rates for even coverage and reduced runoff. Automatic sprinklers with multiple-program controllers are convenient, flexible, and can accommodate several watering schedules.
  • Monitor sprinkler systems for leaks, clogs, and breakdowns. Adjust automatic programming as weather patterns change. Some cities offer irrigation audits through their energy conservation departments.

1. How do I know if the lawn needs water?

Most grasses take on a dull, dark appearance and leaves begin to roll when they need water. Two easy ways to know when to water:

  • Do the “footprint” test
    Walk across your lawn, then turn around and look for your footprints. If you can see them, your lawn is stressed and needs water. If you can’t see them, if the grass springs back up quickly, then your lawn does not need additional water.
  • Dig a hole and feel the soil to see if it is moist.
    This is the most accurate method. Use a spade, shovel, trowel or soil probe. Dig at least four to six inches deep. If there is any moisture at all in the sample, your lawn does not need water.

2. How often do I water?

Grass Species (Adapted Region) How often To Water

sprinkler-headThe number in () is the “adapted region.” These recommendations are for grass planted in its adapted region. If the grass is not adapted to your region, consider replanting with one that is.

  • Buffalograss (3,4,5) – Every 2-5 weeks
  • Bermudagrass (6) – Every 7-10 days
  • Centipede (1) – Every 7-10 days
  • Zoysia (3.4.5) – Every 7-10 days
  • Carpetgrass (1,2) – Every 5 days
  • St. Augustine (1,2,5) – Every 5 days
  • Tall Fescue (4) – Every 4 days
  • Bluegrass (1,4) – Every 4 days

Adapted Regions: 1-East Texas; 2-South Texas; 3-West Texas; 4-North Texas; 5-Central Texas; 6-Statewide

3. How much do I water?

Procedure for figuring out how much water your grass needs.

  • Set 3-5 empty cans at different distances from the sprinkler with the last can near the edge of the sprinkler coverage.
  • Run the sprinkler for 30 minutes.
  • Add the inches of water in all cans and divide the total inches by the number of cans to obtain an average.
  • Multiply the average by two to determine how many inches of water are applied in an hour.
  • Use the list below to determine how many inches of water to apply every fifth day to Bermudagrass during June, July, and August. Buffalograss needs about 25 percent less water and St. Augustine needs about 15 percent more.
  • Subtract any rainfall from the amounts given in the list to determine how much water to apply.

Paris, Tyler, Bryan, Houston areas – .75 inch in 5 days
Sherman, Waco, Austin, San Antonio, Corpus Christi areas – 1-1.5 inch in 5 days
Abilene, Amarillo, Midland, El Paso areas – 1-1.5 inch in 5 days
San Angelo, Laredo areas – 1.5 inch in 5 days

Irrigation System Tips

Automate your sprinkler system. Add an electronic controller or timer to water your landscape at the precise time you want for maximum benefits. Multiple-program controllers can accommodate several planted zones and time schedules. Your irrigation system will work most efficiently if plants have been grouped according to their water requirements. Adjust timers for seasonal conditions.

Use low-volume, matched-precipitation sprinkler heads. Low-volume sprinklers reduce evaporation due to wind, and slow the water’s delivery rate allowing the soil more time to absorb the water. Matched-precipitation sprinkler heads provide the most even coverage.

Check your sprinkler system for leaks. A leaky system wastes a lot of water fast. Look for these signs of trouble: broken or clogged sprinkler heads; muddy spots in the soil or lawn; lowest sprinkler leaks constantly (valve problem); valve box filled with water; water meter always running.

Install a drip irrigation system for gardens, shrubs, trees, and planters. This flexible, low-volume, low-pressure watering system uses plastic pipes and emitters and applies moisture only where it is needed, at the plant root zone. A drip system typically uses 40 to 60 percent less water than conventional methods.

For best results, water when there is no wind and the weather is cool, usually between the hours of 2 a.m. and 8 a.m. Evaluate the rate at which the soil absorbs water to determine the best way to water and minimize runoff.

Install a rain shutoff device to override the sprinkler system when it rains. The controller will resume watering when rainwater collected in a special pan has evaporated.

Use an automatic moisture sensor to determine when your lawn needs watering. An automatic sensor will trigger sprinkler operation only when soil moisture falls below a certain level.