To winterize your sprinkler system, shut off the irrigation water supply and turn off the controller. Release pressure in each zone, then drain the lines. Some systems also need a blowout with compressed air. Finish sprinkler system winterization before freezing weather settles in so trapped water doesn’t damage pipes or other irrigation components.
Get your sprinkler system ready before the first freeze
If fall temperatures are dropping and your sprinklers are still running, it’s time to start planning for winter. Turning off the controller stops scheduled watering, but water may remain inside the irrigation lines.
The right winterization approach depends on how your system drains. The steps you take to winterize sprinkler system lines also depend on where water tends to remain after you shut off the supply. If you’re unsure what your setup needs, professional sprinkler winterizing services help clear remaining water before freezing weather arrives.
Why sprinkler winterization matters
Water left inside irrigation components may freeze as temperatures fall. As that water expands, it puts pressure on pipes and fittings. It may also damage sprinkler heads or exposed equipment.
Proper irrigation winterization removes water from vulnerable parts of the system before cold weather settles in. It also gives you a chance to notice visible problems before the yard goes dormant.
When should you winterize your sprinkler system in Utah?
If temperatures drop below freezing before you’ve winterized, that doesn’t necessarily mean the cold damaged your sprinkler system. The risk depends on how cold it gets and how long those temperatures last.
In northern Utah, fall lawn watering usually tapers off through September and early October as temperatures cool. The northern Utah turfgrass calendar also notes that weather conditions should guide seasonal watering decisions.
Watch the overnight forecast as fall progresses. Good irrigation winterization timing gives you room to shut the system down before freezing nights become the norm, rather than waiting for a hard freeze to force a last-minute decision.
Does every sprinkler system need a blowout?
Not every irrigation system drains the same way. Some systems use manual drain valves. Others rely on automatic drains. Many pressurized systems also require a blowout to clear remaining water from the lines.
That’s why advice from a neighbor may not fit your property. Your system may use a different layout or drainage setup, so that sprinkler system winterization may look different from one home to the next.
If you don’t know how yours works, start by locating the irrigation shutoff and valve boxes. Look for drain points and exposed backflow equipment to better understand how the system releases water before winter.
How to winterize your sprinkler system
1. Shut off the irrigation water supply
Start with the valve that feeds your irrigation system. Turning off the controller only stops scheduled watering. It doesn’t stop water from entering the lines.
If you recently moved in, identify the irrigation shutoff before freezing weather arrives.
2. Turn the sprinkler controller off
Set the controller to its off or rain setting so it doesn’t run during winter. Leaving it powered may preserve your programming for spring.
3. Release pressure and drain the system
Open the appropriate valves or drain points to allow water to leave the irrigation lines. Utah State University recommends shutting off the main irrigation supply and releasing pressure in each zone. It also recommends draining the system or using compressed air when the setup lacks drain valves.
One open drain may not clear the entire system, especially where low sections hold water.
4. Blow out the lines when your system needs it
A blowout uses compressed air to push remaining water through the sprinkler heads. Work zone by zone, so water doesn’t stay trapped in the lines. When you winterize sprinkler system lines this way, the compressor setup matters.
Air pressure and airflow both matter. Too much pressure may damage irrigation components, while too little airflow may leave water behind. The right setup depends on the system’s size and design, making proper sprinkler winterization especially important when using compressed air.
If you lack the right equipment or experience, professional irrigation winterization removes much of the guesswork.
5. Protect exposed components
Backflow assemblies and other above-ground parts are directly exposed to cold air. Make sure your shutdown addresses those areas instead of focusing only on buried sprinkler lines.
6. Work through every zone
Clear each irrigation zone rather than stopping after one section looks dry. If you notice a damaged head or a leaking valve, make a note of it so you know what needs attention before winter or during spring startup.
Problems that arise during winterization may also indicate a need for sprinkler system repair and service before regular watering resumes.
Know how your irrigation system drains
You don’t need to understand every fitting in a valve box, but you should know the basic parts involved in shutdown. Knowing how the system drains also makes it easier to plan irrigation winterization each fall. Before you winterize sprinkler system components, identify the following:
- The main irrigation shutoff
- The controller and valve boxes
- Any drain points
- The backflow assembly, if present
- The blowout connection, if your system uses one
This matters even more if you recently bought the home. Understanding the setup now makes future fall shutdowns much easier.
What about secondary water and drip irrigation?
If you use secondary water, don’t assume the district’s seasonal shutdown drains your property. The district stops the incoming supply, but water may remain in your private lines.
Drip irrigation also needs attention. Tubing and filters may hold water after regular watering stops. So may regulators or exposed fittings. Include those areas in your winterization plan for the irrigation system, rather than focusing only on turf zones.
If you’re unsure what the setup requires, have someone review it before freezing weather arrives.
What if freezing temperatures arrive before you winterize?
If temperatures only dip below freezing for a short time, your sprinkler system may come through without damage. The real risk depends on how cold it got and how long those temperatures lasted.
Don’t assume it’s too late. Shut off the irrigation supply and winterize sprinkler system components as soon as practical. Check exposed equipment closely because cold air reaches it sooner than buried lines.
When spring arrives, watch for leaks or pressure changes as you restart the system.
Common sprinkler winterization mistakes
Most sprinkler system winterization problems start with assumptions. Homeowners often think shutting off one part of the system takes care of everything.
Watch for these common mistakes:
- Turning off the controller without shutting off the irrigation supply
- Assuming a secondary-water shutdown drains the private system
- Forgetting drip irrigation
- Using compressed air without understanding the setup
- Skipping a zone because another zone already looks dry
- Waiting until repeated freezes have started
A careful shutdown gives the system a better chance of making it through winter without freeze-related damage.
What should you check when you start the system again in spring?
When temperatures warm up, turn the water back on carefully and run one zone at a time.
Look for broken heads and unexpected water. Pay attention to weak spray patterns or unusual pressure. If something looks different from last season, address it before regular watering begins.
Winterization protects against cold-weather damage, but it doesn’t repair existing problems. Spring startup also gives you a chance to see whether your irrigation winterization worked as expected or whether part of the system needs attention.
Frequently asked questions
Do all sprinkler systems need to be blown out?
No. The drainage method depends on the system. Some setups use manual or automatic drains, while others require compressed air. Understanding your setup helps you choose the right sprinkler system winterization approach before temperatures drop.
How cold does it need to get before sprinkler pipes freeze?
No single temperature guarantees damage. Pipe depth and exposure affect the risk. The length of the freeze matters as well. Finish winterization before freezing nights become regular, rather than trying to predict an exact threshold.
Is shutting off secondary water enough for winter?
Not always. A seasonal shutdown halts the incoming water supply, but it may leave water in the irrigation lines on your property. Check how your private system drains.
Do drip irrigation lines need winterization?
Yes. Include drip components in your fall shutdown, as tubing and fittings may retain water. Your setup determines the best drainage method.
Should I unplug my sprinkler controller for winter?
Usually, leave the controller powered and use its off or rain setting. Check the manufacturer’s instructions if your controller requires something different.
Prepare your sprinklers for winter with All Seasons Landscaping
Fall weather changes quickly in Utah, and an early freeze leaves less room to deal with an unfamiliar system. If you aren’t sure how your system drains or you’d rather have a professional handle the blowout, All Seasons Landscaping is ready to help.
We provide seasonal sprinkler service for properties in Utah and go through the system before winter settles in. Contact All Seasons Landscaping to schedule service and get your irrigation system ready for colder weather.