Sprinkler Tips From a Pro: Spokane's Season-by-Season Guide

Sprinkler systems in Spokane work hard: months of heavy use through a hot, dry summer, then a winter cold enough to crack anything still holding water. This guide walks through the year, from spring start-up to fall blowout, with what to check, what to adjust and when to call in our sprinkler and irrigation team.

What sprinkler maintenance does a Spokane system need each season?

Start the system up in spring, usually April or May, and adjust run times as summer heats up. Cut back in September, then blow the system out before the first hard freeze, usually in October.

Timing shifts with the weather each year, so treat the months as a guide and watch the forecast.

How should you start up your sprinklers in spring?

Wait until hard freezes are behind you, which in Spokane is usually April or May. A late cold snap can crack a freshly filled backflow preventer, which often sits above ground where it's most exposed. Then:

1. Close any drain valves that were opened for winter.
2. Open the main valve slowly. Turning the water on all at once sends a pressure surge through empty pipes that can crack fittings or blow heads apart. Open it a little at a time and let the system fill.
3. Wake up the controller. Replace the backup battery, check the date and time and review the program. Winter power outages can reset it.
4. Run every zone and walk it. Look for heads that don't pop up, broken or tilted heads, geysers, weak spray, heads watering the sidewalk or the house and soggy spots that point to a leak underground.
5. Fix problems before the heat arrives. A broken head or leaking valve in May becomes a brown lawn in July.

If a zone won't turn on, the water won't shut off or the backflow preventer is leaking, book a spring start-up and inspection and let a tech find the cause.

How much should you water your lawn in a Spokane summer?

A good starting point for most Spokane lawns in July and August is roughly 1 to 1.5 inches of water a week, counting any rain, adjusted up or down for how the lawn responds. How long that takes depends on your heads. Spray heads put water down much faster than rotors, so the same run time can deliver very different amounts.

Find out what your system actually puts down with a catch-cup test:

1. Set a few straight-sided cans or cups around one zone.
2. Run the zone for 15 minutes.
3. Measure the water in each can and average it.
4. Multiply by four to get inches per hour, then set run times to hit your weekly target.

A few rules of thumb:

• Water early in the morning. Less water is lost to heat and wind, and the grass dries off during the day.
• Water deeply and less often. We want the water going down, because the roots follow it. Deeper roots handle the heat better, and a few longer waterings beat a short one every day.
• Split run times on slopes and hard soil. If water runs off before it soaks in, run each zone in two or three shorter cycles an hour apart.
• Adjust through the season. Bump run times up for July and August, then back down in September. Many controllers have a seasonal adjust setting that changes every zone at once.

Why does one part of the lawn stay brown?

A brown patch in a watered lawn is usually a coverage problem, not a run-time problem. Before you turn up the whole zone, watch it run and look for:

• A head that's clogged, broken or not popping up fully
• A head knocked out of line and spraying the fence, sidewalk or house
• Grass grown up around a head and blocking the spray
• A head sunk below the turf by mowers and foot traffic
• Low pressure across the zone, which can mean a leak or a valve problem

Turning up the whole zone to fix one dry corner overwaters everything else. Adjusting, cleaning or replacing the head is the real fix. Mowers and foot traffic knock heads around all summer, so a mid-season walk-through is worth the ten minutes.

If water beads up and runs off even where coverage is good, the soil may be compacted. See when to aerate your lawn in Spokane.

When should you blow out your sprinklers in Spokane?

In fall, once you're done watering and before the first hard freeze. In the Spokane area that usually means October. Shutting off the water isn't enough. Water left in the pipes, valves, heads and low spots expands when it freezes and can crack them, along with the backflow preventer.

Taper off before the blowout: cut run times back in September as the nights cool, but keep watering through a dry fall until the grass slows down. After the blowout, turn the controller off or to its rain setting so it isn't cycling valves on an empty system all winter.

Fall is the busiest stretch of the year for sprinkler crews, and an early cold snap won't wait for your calendar. Book early with our sprinkler blowout and winterization service.

When should you call a sprinkler pro?

Plenty of sprinkler care is homeowner work: adjusting heads, setting run times and keeping grass trimmed back from the heads. Call a pro when you see:

• A zone that won't turn on, or won't turn off
• Water bubbling up, or a spot that never dries
• A sudden drop in pressure
• A leaking or cracked backflow preventer
• Controller or wiring problems you can't track down
• An old system that needs new heads, a new controller or a redesign

Sprinkler repair from Automated Lawn & Pest Control covers broken heads, leaks, valves, wiring and controllers across Spokane, Spokane Valley and Coeur d'Alene. If the system is past fixing, we also design and install new sprinkler systems. Request a free quote or call (509) 818-1831.