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.
Apply some wetting agent to help the water 'slip through' that dead layer. Feed with Eco red and raise your mowing height to stimulate root growth. Some Eco Vital or Seasol will help both root growth and help your lawn cope with the recent stress.
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.
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!
Mowing a lawn in the middle of a summer heatwave is one of the worst things you can do to it. When temperatures reach around 85 degrees, grass, like many other green plants, begins to suffer – especially cool-season grasses such as Kentucky bluegrass, perennial ryegrass, and fine fescues.
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.
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.
If the plants pull out from the ground easily, they're probably dead. If the roots hold fast when pulled, the plants are dormant. You will also see the difference when you start to water or when rain returns as moisture will revive brown grass. However, it will not bring dead grass plants back to life.
Drought Stress
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.
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.
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.
Fertilizer & Herbicide Treatments
Avoid applying fertilizer to a drought stressed lawn – it will not cause the grass to green up and can actually increase overall stress. Wait until mid- to late-August to make that fall application.
It's Noticeably Wilting
One of the earliest and most obvious signs of dehydration in grass is wilting, when blades begin to curl over instead of standing up straight. If you don't take action right away, you will soon see the grass start to change color (which we discuss in more detail below).
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.
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.
WATER BEFORE DAWN
It is often recommended that you water your lawn early in the morning, as early as 4 am and no later than 10 am. During extreme heat, watering should be done no later than 7 am.
Avoid watering grass on a hot afternoon when it's 95 degrees or higher. The best time to water grass is at dawn or in the early evening. Water deeply three times a week instead of a little water daily. Test whether your sprinkler system is watering your lawn evenly.