With the high temperatures and lack of rain over the past two to three months, we are now starting to receive more calls at the Extension Office from people with lawns suffering damage.

When checking the damage presently seen in lawns, there are several factors that need to be considered. These include determining the cause of the damage: drought, disease, insects or poor cultural management.

To avoid drought killing the grass, lawns may need to be watered at least once a week and sometimes twice a week. We need to water as needed. Irrigation frequency depends on seasonal rainfall and soil type. The old “one inch of rain or irrigation per week” means little. Heavy clay soils need up to 2 1/2 times as much irrigation water as sandy soils when dry. When the lawn first shows any droughty or off-color areas, water immediately. Water well but infrequently so the root zone is moistened to about 4 to 6 inches down.

This may require watering in consecutive, short cycles until the wetting depth is achieved. By watering in cycles, we keep most of the irrigation water on the lawn and out of the gutter. After watering, allow several hours to soak in and reach a stable state, then check the final wetted zone.

Many gardeners tend to water lightly every day during dry weather, but the water doesn’t penetrate deeply into the soil. Because roots only grow where there is adequate moisture, this results in a shallow root system. Shallow-rooted plants are unable to tap reserves of water deeper in the soil and are prone to drought stress in even brief dry periods. Eventually, your plants become dependent on you to water them constantly. And watering every day also increases the chances of foliar diseases and root or crown rots.

The most common and popular method of landscape irrigation is sprinklers, which are also the only practical way to water lawns and large trees. Installed underground systems and hose-end sprinklers are the two basic types.

Underground systems are effective and very convenient, but they’re expensive to purchase and generally must be installed professionally. Professional landscape irrigation system installers must be licensed by the Louisiana Department of Agriculture and Forestry. Ask to see a copy of their license to make sure the company or individual that installs your system is reputable and knows what they are doing.

Most home gardeners use hose-end sprinklers. They are less expensive and do not require professional instillation. But they’re inconvenient to use because they must be moved to cover large areas and generally must be picked up after use.

To figure out how long to leave your sprinkler on to apply one inch of water, first place several empty cans in the spray pattern of the sprinkler. Turn on the sprinkler and check the time. When about an inch of water has accumulated in most of the cans, check the time again. That’s how long it takes your sprinkler to apply an inch of water – and about how long you should leave it on to thoroughly irrigate an area. The best check of how thoroughly an area has been watered is to go back about 15 minutes after watering and dig into the soil with a trowel. Did the water penetrate 4 to 6 inches? Check several places.

As the summer progresses, chinch bugs or mole crickets may be a problem in your lawn. If you suspect these insects, you must examine the grass and look for the insects. If you do not find the chinch bugs or mole crickets, then you should suspect other reasons for the damage. If you do find the insects, then you should treat with a recommended insecticide. Insecticides to treat for these insects are available at most home and garden centers.

Improper mowing can also cause stress to your grass. Mowing reduces leaf area and forces denser growth. Improper mowing creates a nutritional shock to the plant that will thin the stand. Never take more than the top one-third of the foliage off at any one mowing to minimize shock from carbohydrate loss. St. Augustine is cut to 2 1/2 inches in sun and 3 inches in shade. Centipede is cut to 1 to 1 1/2 inches (1 1/2 in shade) for best health and appearance. Don’t forget to sharpen that mower blade twice in a season. A fairly sharp blade gives an attractive surface and healthier lawn. It also reduces turf water loss, thus holding off drought effects.

Mid summer is the time to grow and thicken your lawn. Some insects such as chinch bugs and army worms may be of concern, so scout at first signs of discoloration and treat if needed. Diseases such as leaf spots and take-all patch may be a concern, especially if times are stressful to the turf. Weed control on these grasses is normally done in the cooler fall, late winter and especially spring to avoid turf damage. Remember, it takes a lot of work and proper management to maintain a nice, healthy lawn! For more information on Lawn Care contact your County Agent or visit the LSU Ag Center website at lsuagcenter.com.

David Pichon is a County Agent with the LSU Ag Center. He assists homeowners in St. Charles and St. John Parishes with their Home Gardens and Home Grounds. You can contact him by phone at 985-785-4473 or by e-mail at: dpichon@agcenter.lsu.edu.