When to shutdown your irrigation system
By Jim
When to Shut Down Your Irrigation System (And Why the Timing Matters on Cape Cod)
Once the days start shrinking and those first chilly nights show up, it’s tempting to just forget your irrigation system is even running. Don’t. Shut it down at the wrong moment — or the wrong way — and you could be looking at a repair bill next spring that didn’t have to happen.
Out here on the Cape, there’s no fixed date for the end of irrigation season. The weather decides, not the calendar. Here’s what homeowners should keep in mind.
Why Timing Actually Matters
Water expands as it freezes, and irrigation pipes are full of the stuff. Let a hard frost catch your system before it’s drained and shut off, and that expanding ice can split pipes, valves, and backflow devices — both underground and inside the irrigation box itself. Often you won’t even know the damage happened until you fire the system back up next spring.
That said, shutting things down too soon isn’t the end of the world. You’ll just end up hand-watering more during any dry spells, and your lawn might go into winter a bit more stressed than it needs to. The trick is landing in that middle ground: late enough that your lawn and plantings stay healthy through the fall, early enough that you’re not racing the first freeze.
The Rough Rule of Thumb
Around here, that window usually lands somewhere between mid-October and early November — basically once nights start reliably dipping near or below freezing. Key word: usually. No two falls play out quite the same way, and a mild October can easily push things back.
A few clues that shutoff season is approaching:
- Overnight temperatures keep bumping up against 32°F
- A stretch of real cold is showing up in the forecast
- Your lawn and plantings have clearly slowed down for the year
“Turning It Off” Is the Easy Part — This Isn’t
A lot of DIY winterization attempts fall apart right here. Doing it properly actually involves:
- Shutting off the water supply feeding the irrigation system
- Draining the lines so there’s no standing water left to freeze
- Blowing out the system with compressed air, clearing water from the pipes, valves, and sprinkler heads
- Protecting the backflow preventer — usually the priciest part to replace, and often the first thing to fail
Whatever water is still sitting in the lines is precisely what leads to freeze damage in the first place.
Let Us Worry About the Timing
Come fall, our irrigation crew is tracking the forecast across the Cape, lining up winterizations before the cold gets a chance to cause trouble. That’s one more thing off your plate.
Ready to get winterized? Get in touch with our irrigation team and grab a spot on the schedule before the frost beats you to it.