Yes, assuming you have an irrigation controller with a percentage adjust feature. It is a good idea to use the calculator to confirm that your current watering program is reasonable. Once you are certain that you have an efficient watering schedule for the peak watering months of July and August, you can input the Watering % Adjust information to keep your watering schedule current as climatic conditions change. However, if the program in your controller is not efficient, following the Watering % Adjust values will merely shift the inefficient program up and down, with an end result of inefficient watering.
If you have a controller that lacks the percentage adjust feature, the Landscape Watering Calculator is definitely a must. It will not only provide a starting schedule, but it will also provide a long-term schedule to follow over time. Like the Watering % Adjust, the Landscape Watering Calculator should be used together with ongoing observation of the health of your landscape to make schedule adjustments to overcome signs of a stressed landscape.