The key to efficient irrigation is to know when to water, how much to water, and whether you need to water at all. Once established, many landscape plants hardly need supplemental watering during the irrigation season. For lawns and gardens that need irrigation, use the following tools to help you water efficiently:

Consult the Irrigation Water Management Society's Watering Index to adjust your watering schedule throughout the summer. During the watering season, the index fluctuates with changing weather conditions and length of day. Simply adjust your watering by the index: a 50% index means you should water half as much, a 75% index means you should water 3/4 as much as you would in July.

If you have an automatic sprinkler system, set the watering schedule for the hottest, driest time of year and use the "Water Budget", "Percent Adjust" or "Seasonal Adjust" feature found on most modern controllers to enter the Watering Index with major weather changes. Be sure to have a rain sensor installed, to turn the system off when it rains.

• Use the Water Budget Calculator to determine your landscape's watering requirements.
• Create a customized watering schedule based on your plantings and watering system with the Sprinkler Calculators.