Figuring out how long to water

how to use our charts for your landscape

The Inland Valley Garden Planner provides irrigation schedules for different plants and plant palettes. They give recommendations in units of inches of water, like, for example if the entire area of the garden was covered in 1” of solid water, then is allowed filter into the soil. We do this, because this is an approach that works no matter the size of your area of landscape.

To make this information work for you, use this guide to translate the recommendations from the chart into the number of minutes to run your irrigation system. Because the rate at which each area of your system puts out water varies based on both the layout of the system and the products used, it takes some measurements to get good numbers.

Not to worry, we will walk you through the whole process and provide some handy calculators to do the math for you!

Before you get started

Run the irrigation for the areas you will be measuring

This is done to make sure there are no clogged or broken sprinklers or leaks. If anything is broken or clogged, fix it before proceeding.

If using drip irrigation, check for leaks buried in mulch

This is done by running the system and walking the area both looking for visual leaks, or for smaller leaks, listening for a hiss or other unusual sounds.

It is usually best to perform this test for each “zone” in your landscape. A zone is an area that is all watered when one valve of your irrigation system is running. Each zone is told how long and how often to water by an irrigation controller, sometimes also called a timer. This process takes a while, but is the best way to ensure you will be watering for the appropriate amount of time.

Calculating your irrigation schedule

Depending on the type of irrigation you have in your yard (spray, rotor, or drip irrigation), different methods are available for you to use to calculate your irrigation schedule.

If you have a spray or rotor system

You can perform a simple test with mason jars or tuna or cat food cans and use one of our online calculators to tell you how long to water to apply a desired amount (as recommended in our charts, for example 1”).

Follow our step-by-step example

If you have a drip irrigation system

You can do a test by measuring the area (in square feet) of an irrigation zone in your garden. Then you will take readings on your water meter before and after running the system. You will use one of our online calculators to enter that information and it will tell you how long to water to apply a desired amount (as recommended in our charts, for example 1.”).

Follow our step-by-step example