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.
To correctly water your lawn look at a thermometer outside. If it's 70-80 degrees outside try watering 2-3 times a week. During the spring your lawn will be fairly easy to manage so you don't have to water all the time. In the blazing summer, when temperatures are between 90-100+, try watering 3-4 times a week.
During really hot weather, water your vegetables at least two to three times a week. Watering the garden deeply is critical. The water must go down, down, down to encourage deep roots and get away from the hot soil surface.
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.
There is no way to revive dead grass, but you can nurture brown or even yellowing grass back to health. If you live in an area that gets a lot of rain, then you can let mother nature hydrate the lawn on your behalf.
For example, mowing every 4-6 days may be sufficient, but if your grass is experiencing heat stress or has become dormant, you won't need to. The most important thing is to avoid cutting more than ⅓ of the blade off at a time. This is especially important in the heat of the summer.
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.
Lawn Care for Heat-stressed Grass
Lawn watering - make sure to water your lawn adequately to provide it with proper hydration. A properly hydrated lawn can cool itself effectively through transpiration. Reduce foot traffic - avoid causing further damage to weak and sensitive grass blades during extreme temperatures.
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!
Warm season grasses should be fertilized from the time of green up in spring through September. So, if your lawn is a warm season grass go ahead and fertilize in summer to keep it nice and green. (About a pound of nitrogen for every thousand square feet every 4 to 6 weeks should do it.)
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.
It's a common misconception that watering dead grass will bring it back to life. The truth is, when you water dead grass, it can actually make the situation worse. It can cause the roots in the ground to rot and decompose faster than they would if left alone.
If your grass is turning brown despite watering, it's possible that you may have a problem with disease, caused by microscopic living organisms. These include bacteria, fungi, and nematodes, among others.
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.
Vegetables and fruits that are developing fruit during a heat spell need regular watering to ensure good production. Vegetables typically require daily watering during summer weather, but may need a second watering when temperatures are extremely high.
Watering infrequently means only watering when the grass is dry. Try to water early in the morning when your lawn can get the full benefit of hydration before the sun dries it out by mid-day. Watering in the evening leaves the water standing overnight with nothing to dry it up which can lead to mold and fungus.
When working in the heat, drink 1 cup (8 ounces) of water every 15–20 minutes. This translates to ¾–1 quart (24–32 ounces) per hour. Drinking at shorter intervals is more effective than drinking large amounts infrequently. Do not drink more than 48 oz (1½ quarts) per hour!
It is ideal to water lawns about one inch of water per week. To determine how long you need to water to get one inch, place a plastic container in your yard and set a timer. On average, it will take 30 minutes to get a half inch of water. So, 20 minutes, three times per week will give a lawn about an inch of water.
Most lawn experts recommend watering your grass until the soil or ground temperature reaches the 40-degree Fahrenheit mark.