Watering properly will help your lawn grow deep roots that make it stronger and less vulnerable to drought. Most lawns are watered too often but with too little water. It’s best to water only when the lawn really needs it, and then to water slowly and deeply. This trains the grass roots down. Frequent shallow watering trains the roots to stay near the surface, making the lawn less able to find moisture during dry periods.
Every lawn’s watering needs are unique: they depend on local rainfall, the grass and soil type, and the general health of the lawn. But even in very dry areas, no established home lawn should require daily watering.
Try to water your lawn in a way that imitates a slow, soaking rain, by using trickle irrigation, soaker hoses, or other water-conserving methods. It’s also best to water in the early morning, especially during hot summer months, to reduce evaporation. Apply about an inch of water–enough that it soaks 6-8 inches into the soil. Then let the lawn dry out thoroughly before watering it again.
The best rule is to water only when the lawn begins to wilt from dryness–when the color dulls and footprints stay compressed for more than a few seconds.