How Much Should You Water Your Landscape During Monsoon Season in Flagstaff?

One of the questions we hear frequently during summer in Flagstaff is surprisingly simple:

“It rained yesterday. Do I still need to water?”

The answer? It depends.

Monsoon storms can give our landscapes some much-needed moisture, but one afternoon of rain doesn't necessarily mean your entire property received enough water to turn the irrigation off for the week.

Knowing when to adjust your irrigation — and when not to — can make a big difference in the health of your landscape.

Don't Assume Rainfall Reached Everything

Summer storms in Northern Arizona can be incredibly localized. One neighborhood may receive a significant amount of rain while another part of town stays relatively dry.

Even within your own property, rainfall doesn't always reach every plant equally.

Tree canopies, rooflines, walls and other structures can create areas that receive considerably less rainfall than exposed portions of the landscape.

Rather than automatically shutting your irrigation system off every time it rains, take a look at what actually happened on your property.

Check the Soil, Not Just the Weather App

One of the simplest ways to determine whether your landscape needs water is to check the soil.

Surface soil may look dry while moisture remains farther down — or the opposite can be true after a brief storm that wets only the top layer.

Trees, shrubs and smaller plants also have very different root zones. University of Arizona Extension recommends deep, less frequent watering to encourage deeper root development and notes that trees have substantially deeper root zones than lawns or garden areas.

That means irrigation should be based on what you're watering, not simply whether rain appeared in the forecast.

Different Plants Have Different Needs

A mature tree and a newly planted perennial shouldn't necessarily be watered on the same schedule.

Newly installed plants generally require closer attention while their root systems establish. Established plants may be able to go considerably longer between watering.

Plant selection matters, too.

Plants that are well adapted to Northern Arizona conditions often require less supplemental water once established than plants that are poorly suited to our climate.

That's one of the reasons thoughtful plant selection and proper irrigation design work hand-in-hand when creating a successful Flagstaff landscape.

Too Much Water Can Be a Problem, Too

The instinct during summer is often to worry about landscapes becoming too dry.

But continuously running irrigation through periods of significant rainfall can create the opposite problem.

Consistently saturated soil can be stressful for plants, and unnecessary irrigation wastes water.

Instead, think of your irrigation controller as something that should change with the season rather than a system you set in spring and forget until fall.

The City of Flagstaff actively promotes water-conscious landscaping and currently offers resources for homeowners interested in reducing landscape water use.

And When Monsoon Season Begins to Wind Down...

This is where homeowners can get caught.

We get accustomed to those afternoon storms helping our landscapes along — and then suddenly they become less frequent.

As we move toward the end of summer, continue watching soil moisture and adjust irrigation again as rainfall decreases.

Your landscape's water needs aren't determined by a date on the calendar.

They're determined by the weather, soil, plant material, exposure and the needs of your individual property.

Need Help With Your Irrigation System?

A properly functioning irrigation system makes it much easier to give your landscape the water it needs without wasting it.

Agassiz Landscape Group provides irrigation installation and seasonal servicing in Flagstaff, from troubleshooting and repairs to seasonal system care.

If something doesn't seem right with your irrigation — or you'd like professional help caring for your landscape throughout the season — contact our team. We'd be happy to help.