How Long to Water a Lawn at Night

How Much Water Per Week

• Most grass types need 1 inch of water a week to survive, according to Ohio State University. However, you can judge by the appearance of your lawn when determining when to provide water. Grass needs water when it looks wilted, takes on a blue-gray color or doesn't bounce back after foot traffic, according to the University of Florida. To tell if your grass has received at least 1 inch of water in week, leave tuna or coffee cans in the yard. Measure the amount of water in the cans before applying water.

How Long to Run Water

• Typically, you should set sprinkler systems to run for one to two hours in order to provide 1 inch of water, Ohio State University advises. It is important to nail down the correct amount of time to set your irrigation system to avoid over- or under-watering. Set at least 10 cans around your yard. Turn your irrigation system on and take note how long it takes for 1 inch of water to accumulate in your cans.

Checking the Sprinkler System

• Check all the cans in the yard to ensure that all of your sprinkler nozzles are working properly. Look for areas where water is puddling or where the sprinkler nozzle is tilted toward the ground. Make sure that your sprinkler system is not pointed toward your ornamental plants. Landscape plants have different watering requirements than your turf grass. Adjust any nozzles that send water onto streets, driveways or walkways.

Other Factors

• Yards that have succumbed to fungal diseases or white grub infestations may need to dry out. To control some fungal diseases, gardeners can withhold water from their lawns to dry out fungal spores. Furthermore, gardeners can make their lawns less attractive to scarab beetles. Scarab beetles lay their eggs on moist soil. Once these eggs hatch, white grubs eat grass root systems. By allowing parts of your grass to dry out, you prevent these beetles from laying eggs and you dry out existing eggs in the yard.