Sprinklers should be set to run for about 30 to 35 minutes at a time twice a week. Your goal is at least 1″ of water a week for your lawn.
If your sprinkler output is 1½ inches per week, your sprinklers should run for only ⅓ hour or 20 minutes that week (½ divided by 1½). On a twice-weekly watering schedule, run your sprinklers 10 minutes each time.
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.
How Much Water to Use. When watering an established lawn, it's typically recommended to water until the top 6 to 8 inches of soil (where most turfgrass roots grow) is wet. Most lawns need 1 to 1.5 inches of water per week—either from rain or watering—to soak the soil that deeply.
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.
A related question is how often to water your lawn. You do not have to provide the required 1 inch per week all at once. Instead, you can water for 30 minutes twice a week. But some experts advise against extending irrigation sessions beyond that (for example, watering for 20 minutes three different times a week).
Sprinklers should be set to run for about 30 to 35 minutes at a time twice a week. Your goal is at least 1″ of water a week for your lawn. When it's hot and dry, double the water times while still trying to water just 2 or 3 days a week.
Sprinklers generally cover up wider ground and spread out water at a slow yet steady pace, which makes all the soil moisturized evenly and soaked underground. A watering hose takes time to cover space and can clutter the soil if there's too much water.
The answer is that it usually takes up to 30 minutes to get a half inch of water. Watering 3 times per week equals to an inch of water on a lawn. Plants can be watered 1 to 2 times a week in seasons where there is a higher chance of rainfall and less evaporation.
A common rule that is followed for obstructions within 18 inches of the sprinkler deflector is the “three times rule”. This requires sprinklers to be positioned away from obstructions a minimum or three times the maximum dimension of the obstruction.
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.
But life happens and sooner or later the running sprinkler is forgotten – even overnight! Not only does this waste water, it's also tough on the water bill – and can cause irreparable lawn and plant damage. In fact, over-watering can cause just as many problems as under-watering.
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.
The average system uses approximately 15-16 gallons per minute, per station. Here is an easy formula to help you calculate the approximate amount of water you are using each month.
Uses less water
Sprinklers project water into the air and over plants, allowing some of it to drift in the wind or evaporate from leaves. But hand watering allows gardeners to direct water precisely where it's needed, minimizing drift and evaporation.
Most sprinkler systems use around 12 gallons of water per minute. If left unchecked, that could mean a lawn filled with standing water. A general rule of thumb is to water three days a week in the spring and summer and two days a week in the fall and winter.
Not Adjusted to Properly Cover the Right Areas
If one sprinkler head sprays over another one, this leads to overwatering and wasted water and money. Your grass and plants will absorb what they need to survive. Water they don't need will sit and pool on the surface of your grass.
The “Four Times Rule” is really just an extension of the “three times rule” however it covers extended coverage sprinklers and the maximum clearance is 36 inches (0.9144 m).
Nothing should be in that area between the bottom of the sprinkler heads and the imaginary horizontal plane parallel to the ceiling that is 18 inches below. This is done to allow an even and unobstructed spray pattern from the sprinklers when triggered to extinguish the fire.
Aerate to increase infiltration. 6. Water in the early morning (4am to 10am). This allows the grass blades to dry, making them less susceptible to foliar diseases.
With new grass seed, the aim is to keep the soil moist. Waterlogged soil will suffocate the new seeds. It is best to water the grass seedlings 2 to 3 times a day for about 5 to 10 minutes each time.
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.
Can You Water Grass After Mowing? Yes, you can water grass after mowing, however it is healthy to water it but only if it requires it. Watering will help the mowed blades perk up and survive being cut better. Take care not to water a lawn overwatered or from noon till late into the night.