When watering the lawn, apply this amount in a single application or possibly two applications three or four days apart. Avoid frequent, light applications of water, which promote shallow rooting and lush growth. Lush, shallow-rooted turfgrass is less drought tolerant. To determine the amount of water applied by the sprinkler, place several straight-sided cans within the spray pattern. Then measure the amount of water collected in the cans with a ruler.
Dormant lawns are in jeopardy of dying if drought conditions persist over an extended period.
It's best to water the lawn if the turfgrass has been dormant for four to six weeks. Apply 1 to 1.5 inches of water in a single application. This will not cause the grass to green up, but it will keep the turfgrass crowns and roots alive. If the dry weather persists, water the dormant lawn approximately every four weeks.