The Watering Index (%) is a tool to help you adjust watering times for the current weather. The Watering Index is not hyper dependent on local conditions. Watering run times will be different to reflect your particular climate, but the Watering Index generally goes up or down by the same percentage throughout region. The Watering Index (%) suggests when adjustments should be made, but you have to be proactive by paying attention to the health of your landscape. If your plants look stressed after setting your Watering Index (%) on your sprinkler controller (i.e. “Seasonal Adjust” or “Water Budget” feature), then make practical adjustments from there based on what your landscape is telling you. You may increase the Watering Index (%) slightly, or if the issue is specific to a certain sprinkler valve, go back to the sprinkler controller and adjust the runtime for that zone.
For help on how to program your sprinkler controller, consult your controller's instructions, view videos on how to adjust your specific type of sprinkler controller, or contact your landscaping professional