How To: Hydrate Your Lawn
It's always better to water for shorter periods of time more often. This ensures a steady supply of moisture to your lawn. Keep it moist but not wet. A good way to tell if you have a "thirsty lawn" is by footprints. If the grass doesn't spring back after stepping on it, then it is starting to wilt.
The ideal time to water is in the morning hours (5am-10am). Evaporation is minimized and the lawn will utilize the most water. Watering your lawn in the middle of the day or in the evening can cause fungal disease.
If you are on a fertilizer program it is extremely important to water the lawn so the chemical doesn't dry out the grass. Make sure you give time for the fertilizer to absorb into the soil so it's not washed away.
remember:
-soak the soil to the root zone
-do not let thatch build up
-uniform application is very important

Bud Frank's Lawn Care