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.
How Often to Water Your Lawn During Hot Weather. Whether from irrigation or natural rainfall, your lawn needs about 1 1/2 inches of water each week during the summer. For best results, spread out your watering instead of doing it daily. Otherwise, your grass can grow a weak, shallow root system that dries out quickly.
It's tempting to water your lawn in hot weather, especially if your grass is already looking a bit thirsty. But in most cases, you shouldn't water your grass when it's 95°F or hotter because the water will likely evaporate before it reaches the roots.
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.
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.
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!
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 you can water, do so deeply but infrequently. When the water penetrates further into the ground, it's slower to evaporate and encourages deeper root growth, which it turns helps protect the grass during the next heat wave.
Most lawn experts recommend watering your grass until the soil or ground temperature reaches the 40-degree Fahrenheit mark.
Water Early
Cooler temperatures and subtle breezes help to keep evaporation slowed down. Early morning watering is also recommended as watering your lawn during hot parts of the day can add stress to your grass.
In conditions when the heat is just too much for your grass to overcome, it will essentially shut down until cool, moist weather returns. During this condition, you should irrigate your lawn at least once per week. If you have a newly-planted lawn, don't let it go dormant.
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.
1) Watering for Too Long
This should be no more than three times per week. Set a timer for 20 minutes and stick to your schedule, even if you think the lawn needs more water. You don't want to oversoak it.
Most grass needs watering between 20 to 40 minutes at a time. Water your grass one to three times a week in peak growing seasons. Your grass type, region, and amount of rainfall impact watering times. Watch out for signs of too much or too little watering to avoid disease or dead grass.
Most lawns need to be watered no more than three days a week in the spring as well as in the summer and two days a week in the fall. This watering schedule is recommended under normal water supply conditions.
Although a low-cut, manicured lawn might seem ideal, turf grass actually does better in the summer heat when you let it grow a bit. Longer shoots mean deeper roots, which the lawn needs to suck up whatever moisture is in the soil. A higher lawn also shades the soil, minimizing evaporation.
Grass grows particularly fast during late spring and early summer in response to adequate amounts of water and sunlight and warmer temperatures. In the middle of Summer, grass will have less growth due to the excessive heat but as fall begins you'll see it begin to grow again.
On the other hand, watering longer but less frequently, “deep watering,” produces deep roots that mean lawns can better survive periods of drought. The ideal watering schedule is once or twice per week, for about 25 to 30 minutes each time.
Most oscillating sprinklers will put off about one inch of water an hour. That would mean that you would need to water your lawn for one hour, once a week (twice weekly in periods of extreme drought). For less established lawns, you may need to increase the frequency as your lawn's root system becomes more robust.
Water deeply and infrequently (2-3 times per week). Morning watering is highly recommended, as afternoon watering can lead to early evaporation, while night watering can cause various forms of turf disease. Refrain from mowing too low.
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.
It is dangerous to let your sprinkler system go unprepared in freezing temperatures — 32 degrees Fahrenheit or below. If you live in a wintery climate, the best time to start thinking about winterizing your sprinkler system is when temperatures hover around 40 degrees.
In times of extreme heat, 1-2 times each week may be necessary. Know your plants though! Some plants prefer almost zero water during summer (manzanita, Ceanothus, madrone and cistus) and others wilt even when they have ample water (hydrangea, rhododendron). So adjust watering accordingly.