A lot of homeowners are seeing brown patches in their lawn right now and wondering what’s going on. While its possible these issues can be fungal or insect related, the most likely culprit is drought stress. Drought stress occurs when an actively growing lawn is not receiving the natural rainfall or irrigation necessary to sustain the plant life. In these hot and dry summer months, it is important to closely monitor the health of your lawn by maintaining both a consistent watering schedule, and specific mowing height for your lawn and your particular grass type.
Today we will focus on the identifying, diagnosing, and treating drought stress in both Bermuda grass, and St. Augustine.
IDENTIFYING DROUGHT STRESS
These problem areas you are noticing in your lawn are likely experiencing drought damage, which is the direct result of drought stress. Symptoms will typically appear in large sections across your lawn during a very dry and hot season. You may notice that your grass thins, loses color, and that footprints or tracks will remain imprinted in the well trafficked areas of your lawn. Large brown spots will appear, grass leaves may turn a dull grayish color, and leaf blades will begin rolling and folding.
These symptoms will typically appear within 5-7 days, but can appear as early as 3 days or as late as 15, depending on the level of rainfall or irrigation your lawn is receiving, as well as the severity of temperature.
DIAGNOSING DROUGHT STRESS
The symptoms of drought stress can be very similar to those of a fungal infection or an insect infestation, and can be easily misdiagnosed. Both issues may cause brown dry patches in your lawn, but there are several ways to distinguish between the varying possible issues.
If you are dealing with chinch bugs, they will likely be visible in your St. Augustine lawn upon inspection. If you have grub damage, this means the root of your grass has been attacked, killing the plant. In these areas, you will be able to pull up large sections of your turf grass with little to no resistance from the root. If you are dealing with a fungal infection, please note that these fungi thrive in a very dry environment, so you won’t likely see this in an area where irrigation has or can be applied.
The above aggressors are killing your plant; drought stress simply causes your turf grass to go into a dormant state, and the damage can often be rectified.
FACTS ABOUT DROUGHT STRESS
Drought stress typically occurs in the summer months, when irrigation and natural moisture are being most rapidly evaporated, or during particularly dry seasons.
Different turf grasses will react and recover differently from drought damage. Bermudagrass has a relatively high tolerance. When experiencing this stress, grass will turn brown and go into a dormant state. As previously mentioned, this does not mean your plant is dead. In fact, Bermudagrass can recover well with proper irrigation and mowing techniques.
St. Augustine grass has a lesser tolerance to extended periods of drought. This turfgrass has a moderate resistance to damage due to its extensive root system, but a poor ability to go dormant. If exposed to an extended period of drought, you may experience significant loss of plant life, and grass may need to be replanted.
Most turfgrasses found in Texas can recover from a 60 day period of drought damage, Bermudagrass and St. Augustine included. However, just because your lawn is going to recover doesn’t mean it will flourish. Allowing your lawn to experience extended periods of drought will have long term effects in the coming years, and you may experience a thinner, duller lawn in the following growth seasons.
HOW TO AVOID DROUGHT STRESS
Applying specific and particular mowing and watering techniques can effectively treat an area experiencing drought stress, as well as prevent it from recurring in the future. Here are our recommended mowing heights and watering depths for each grass type:
-Watering Frequency: 3 times per week*
-Pop-up heads: 20 minutes per zone
-Rotary heads: 40 minutes per zone
-Grass Height: Grass should be mowed no lower than 1-1 ½ inches during summer months
The goal with your Bermudagrass is to water it with an even 1-1 ½ inches every week, with the highest frequency in the summer months.
-Watering Frequency: 3 times per week*
-Pop-up heads: 15-20 minutes per zone
-Rotary Heads: 30-40 minutes per zone
-Grass Height: Grass should be mowed no lower than 2 ½ - 3 inches during summer months
*If your city restricts your watering to two times per week, please contact us so we can help you set up your sprinklers accordingly.
Although St Augustine is not as resilient to drought as Bermuda, it also does not tolerate a water logged soil. It is important to only water this turfgrass to the extent it requires. When grass shows drought stress symptoms (dull grey color/folded leaves) water to a depth of approximately 6 inches.
The above guides will set general parameters for turfgrass care in our hottest summer months, when watering will need to remain most frequent to avoid the effects of drought stress. Maintaining a healthy mowing height as well as applying general turfgrass care will also be necessary to ensure the continued growth of a healthy, bright, and consistently full lawn.
We hope this guide helps you understand why you’re seeing brown patches in your lawn and how you can prevent it. But if you need our help maintaining a brown patch free lawn that’s green and healthy, or if you just don’t have time to do it yourself, call our expert technicians today. Ask us about our customized lawn care program and get a free quote today!