Cut back on fertilizer, mow high, and leave mulched clippings on the lawn to shade the soil and reduce evaporation. When you set up the sprinklers
, make sure water is being absorbed; if you see runoff or puddles, you're adding water too fast.
According to TOH
landscape contractor Roger Cook, the main question people usually have about watering, is: how much? The simple answer is that lawns require about an inch of water a week. The tricky part is to figure out how to translate that inch of water into minutes on your sprinkler. There's no way around it, you have to measure. Set up your sprinkler as usual and put out a rain gauge, which can be as simple as an empty coffee can. Water for 15 or 20 minutes, then check how much water is in the can. If you water for 15 minutes and get 1/4 inch of water, you know you need four times that amount of time to get to an inch. That means you need 60 minutes of watering a week to keep the lawn healthy. For more of Roger's advice, see Garden Watering Tips