Watering on a hot summer afternoon is a horrible idea. The liquid will evaporate too quickly and may not reach your grass's roots, so heat and irrigation shouldn't go together. Instead, the best time to water grass during summer is in the morning. The ideal time for morning watering is before 9 AM.
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.
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.
In times of extreme heat, it is vital to water your lawn for about 30 to 45 minutes daily. Once the temperatures drop below ninety, you can cut back to watering three to four times a week, until that blissful thunderstorm comes and quenches your lawn's thirst!
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.
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.
Don't water everyday.
The more shallow your grass roots are, the less hearty it will be in hot weather. Instead water about two times per week for longer periods of time. The local lawn companies I have spoke with around my area (North Central Texas) recommend about 20-30 minutes per watering cycle twice a week.
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.
The best time to water your garden in summer is from 6 am to 10 am—before the heat of the day sets in, giving your plants plenty of time to drink up and any moisture on the leaves to dry off before nightfall. What is this? If watering in the morning isn't possible, the next best time is from 4 pm to 7 pm.
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.
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.
It is best to turn on your system during the warmest time of the day when anticipating freezing conditions. Be sure the outside temperature is 40 degrees fahrenheit or above when you run your system. You ABSOLUTELY do not want to run your sprinkler system during a hard freeze as this will cause damage to your system.
Grass needs the benefit of the day to dry and heal before dusk settles. Since mowing your grass in the early morning can damage it and mowing it during the early afternoon can burn it because of all the high temperatures, the ideal time is mid-morning. That is of course if you're free during that time of day.
Typically, most lawn irrigation periods during the summer should last between 25–30 minutes each. This amount of time depends on a lot of different factors though. As previously stated, each irrigation system or sprinkler can deliver different amounts of water and it's important to hit that 1 inch per week requirement.
If the grass is too wet, you shouldn't mow and if it's too dry you shouldn't either. Remember, mowing is a stressful event for your lawn. If you mow when it's already under stress, such as during dry spell or drought, then it will become even more stressed. You don't like to be stressed and neither does your poor 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.
Once your grass has come out of its dormant state, you may be wondering when you should start cutting it again. Generally speaking, if it is below 50 degrees Fahrenheit, it is still considered to be too cold to mow your lawn. The ideal temperatures to mow are between 50 to 80 degrees Fahrenheit.
Whether or not your lawn is dormant, applying fertilizer right now, with the high temperatures we've been having, is not a good idea. Applying either fertilizer or weed killer when it's hot out can damage your lawn. You're better off waiting until later in summer to fertilize.
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.