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Understanding Evapotransperation (ET), the Irrigation Index and Watering Cycles
Please read:
For each zone/station you use on your auto irrigation system:
Step 1. Identify plant types (turf or shrubs/trees) in that zone.
Step 2. Identify the type of heads or watering system for that zone.
Step 3. Add more zones as needed (up to 17) and then click the "Show my schedule" button below.
Watering Cycles. You may notice that your watering schedule requires cycles. This is an important water conservation technique. Cycles per day means that you may need to break up your watering in a given day into smaller increments. For example, you may need to water for 20 minutes each day, but after ten minutes the water begins to run-off because of a slope or tight clay soil. This is when watering in cycles would be beneficial. In the example above it is better to water in two 10 minute cycles (each day) instead of 20 minutes all at once. This helps avoid wasteful run-off and water waste. Do not confuse cycling with irrigation frequency. Some people might be tempted to change their twice a week watering schedule to everyday to avoid run-off, this is a mistake. It is better to stay on your twice a week schedule (or whatever it might be) and break it up into cycles on the same day. Too frequent, shallow, watering causes unhealthy plants that are not drought resistant.
Please note: This sprinkler calculator creates no more than 17 zones.
If you have already completed a watering schedule (or even filled out at least one zone) you can find your schedule here