In high stress periods, light fertilizer applications will keep your lawn healthy or assist in recovery. If the drought is severe enough, let it go dormant. In conditions when the heat is just too much for your grass to overcome, it will essentially shut down until cool, moist weather returns.
The good news is that the plant can stay dormant for a good while before dying so that, if the water is applied, there can be a full recovery in as little as a few days. These pictures show the damage of heat stress. If your lawn looks like this, water it!
When your lawn has heat damaged, it doesn't just turn brown — the dead, brown grass will eventually disappear and reveal the ground beneath it. These bare patches of ground are easily susceptible to weeds. This is why you need to cover bare patches of your lawn with seeds in order to try and regrow the grass.
It can be patchy, turn yellow or brown, or stop growing altogether. At this stage, homeowners may assume that the grass is dead. But actually, this can be a sign of the grass protecting itself from further damage. Rossi explains, “Grasses have to rely on energy that they store in their root system.
During a heat wave—a period of abnormally hot weather that lasts longer than 2 days—it's recommended that you do not mow your lawn.
AVOID MOWING DURING EXTREME HEAT When your lawn is particularly stressed from heat or drought, it can be limited in its ability to recover from mowing and can be damaged even more. Instead, mow the grass after a rainfall or after irrigation day.
Start by raking dead grass spots to loosen the soil and remove the expired blades. Lightly rake the healthy areas to get rid of dying grass and aerate the soil for root stimulation. Once you have the land prepared, take a rotary seed spreader and lay down new grass seed over the dead spots.
Often lawns are made up of several different cultivars or species of grass so a drought stressed lawn may also have a patchy appearance (Figure 1). Individual grass plants can recover and green up again, once the plants get sufficient water.
As the heat starts to put stress on your lawn you may notice full brown blades of grass or grass with brown tips. They may have begun to curl.
Mowing high gives the lawn a deeper and larger root system, keeps moisture in, defends against weeds and keeps the soil cooler. Mowing too short during dry conditions can injure or wear out dormant grasses to the point where they may not come back during cooler conditions.
Between irrigation and natural rainfall, your grass should receive between 1 and 1.5 inches of water each week during the summer. Water deeply every other day for the best results. Your turf should receive about 1/3 an inch of water every two days in order to maintain deeper roots, thus helping protect against drought.
However, if your lawn is heat-stressed, avoid fertilizer products. Lawn fertilizer on a heat-stressed lawn can have the opposite effect and can cause further damage to an already sensitive grass area.
If conditions become hot and dry enough, the lawn may even begin to die out in some areas. This will cause the lawn to look thin, weak, or have many dead patches throughout. Fall is a good time to revive your lawn. As temperatures cool and moisture becomes plentiful, some of the brown patches will likely green up.
Like any plant, grass reacts to summer's high temperatures and lack of water with wilting, browning, or even death. Here's how to detect drought stress: Locate a brown patch, and pull on the grass. If it won't pull easily from soil and is firmly rooted, it's likely brown due to drought.
You'll often see grass looking a little bluish-purple/gray instead of bright green when it's starting to get stressed. Usually this goes hand in hand with the footprints in the lawn symptom. A golden yellow or brown lawn.
Scotts® TurfBuilder® UltraFeed™is an excellent choice for fertilizing lawns that tend to get stressed in the summer. It holds onto nutrients until your lawn needs them, then releases them. Because of this, a single feeding can last up to 6 months.
Water thoroughly
This one is a no-brainer once water restrictions are lifted. Soaking your lawn will help restore the moisture and help with new root growth. Don't forget to water on grass that's growing on any hills where the wind can dry out the lawn. Also on any sloped areas where water may run off.
After they slow down, they will begin to show signs of stress. This could be certain areas starting to brown out and look dead. That's the natural habit of our grasses, they will go dormant (not dead!) during times of heat or drought stress. This is where watering is crucial.
Once temperatures reach 77 degrees, it becomes too hot for root growth, and root growth ceases. When temperatures reach 90 degrees, it becomes too hot for shoot growth and the grasses stop growing and begin to fall dormant, with the surface grass turning a brown hue.
WATERING SCHEDULE
Deep watering helps to encourage deep root growth. Deeper roots stay cooler and stronger to better protect your lawn and garden from heat stress. Allow a deep watering at least once per week, twice if the temperature exceeds 100 degrees or more for several days in a row.
This may seem like a no brainer, but watering grass during extreme heat is the single most important thing you can do to keep it alive. We recommend watering daily with heat like this, but please be sure to abide by local regulations for water usage in your state. It also matters what time of day you water your lawn.