Fall in Colorado means cooler evenings, changing leaves, and the first hints that winter isn’t far behind. For homeowners, it also means it’s time to start preparing landscapes and irrigation systems for freezing temperatures.
One of the most important items on any fall landscape maintenance checklist is an irrigation blowout. Sprinkler systems contain pipes, valves, backflow devices, and other components that can be damaged when trapped water freezes and expands. Winterizing the system before sustained freezing temperatures arrive can help prevent cracked pipes, broken sprinkler heads, and expensive repairs the following spring.
Use this Colorado irrigation blowout checklist to prepare your sprinkler system and the rest of your landscape for winter.
What Is an Irrigation Blowout?
An irrigation or sprinkler blowout is the process of removing remaining water from an irrigation system before winter. Compressed air is carefully introduced into the system to move water out of irrigation lines, sprinkler heads, and other vulnerable components.
Simply turning off your irrigation system isn’t enough. Water can remain trapped in low points, valves, and underground lines long after the last watering cycle.
When that water freezes, it expands. The resulting pressure can damage irrigation components that you’ll then discover when you turn the system back on in spring.
Proper winterization helps protect the system during Colorado’s freeze-thaw cycles and prepares it for a smoother startup next growing season.
When Should You Blow Out Your Sprinklers in Colorado?
Timing an irrigation blowout can be tricky. You want the system winterized before damaging freezes, but shutting it down too early can leave your landscape without adequate water during a warm, dry fall.
For many Denver and Front Range properties, irrigation winterization typically takes place during the fall as overnight temperatures begin approaching freezing. The exact timing varies from year to year and can also depend on your property’s elevation, exposure, irrigation design, and plant material.
Rather than relying exclusively on a date on the calendar, pay attention to weather conditions and plan ahead. Professional irrigation companies become busy as colder weather approaches, so scheduling your service early can help you avoid a last-minute scramble before the first significant freeze.
Your Fall Irrigation Blowout Checklist
1. Inspect Your Irrigation System Before Winterization
Before shutting everything down, walk through your property and take note of how the irrigation system has performed during the growing season.
Look for sprinkler heads that aren’t operating correctly, unusually dry areas, overspray onto pavement, leaking valves, damaged drip lines, or places where water appears to pool.
Documenting these issues now makes it easier to address repairs during the fall or at spring startup.
2. Shut Off the Irrigation Water Supply
The irrigation system’s main water supply needs to be shut off before winterization.
Depending on the property, this may involve an indoor shutoff valve or another dedicated irrigation connection. Properly isolating the irrigation system prevents additional water from entering while it is being winterized.
Because irrigation systems vary considerably, homeowners should know where their main irrigation shutoff is located before cold weather arrives.
3. Protect the Backflow Prevention Device
Backflow prevention assemblies are particularly vulnerable to freezing because they are often located above ground or in exposed locations.
Water needs to be properly removed from vulnerable components, and exposed equipment may require additional protection depending on the system.
A damaged backflow preventer can be costly to replace, making this an important part of professional sprinkler winterization.
4. Blow Out Each Irrigation Zone
Each zone needs to be cleared individually so that water isn’t left sitting in underground lines.
This is where professional service can be particularly valuable. Using excessive air pressure or an improper compressor can damage valves, sprinkler heads, fittings, and other components.
The objective isn’t simply to force as much air as possible through the pipes. The system needs to be winterized according to its design and components.
5. Don’t Forget Drip Irrigation
Drip irrigation is easy to overlook because much of the tubing may be tucked underneath mulch or within planting beds.
However, these systems can still retain water.
If your landscape includes drip irrigation for perennial beds, shrubs, trees, containers, or other plantings, make sure these areas are addressed as part of the winterization process.
6. Adjust the Irrigation Controller
Once the system has been winterized, adjust your irrigation controller appropriately for the off-season.
Depending on the type of controller, this may mean switching it to an off or rain mode rather than completely disconnecting power. Smart irrigation controllers and more complex systems may have manufacturer-specific winter settings.
Taking this step prevents the system from attempting to run after the water has been shut off.
7. Disconnect Garden Hoses
Your irrigation system isn’t the only outdoor water source that needs attention.
Disconnect hoses from exterior faucets before freezing weather. Leaving a hose connected can trap water and contribute to freeze damage.
Drain hoses before storing them for winter, and make sure exterior faucets and other outdoor plumbing components receive appropriate winter protection.
Don’t Stop Watering Your Landscape Just Because the Sprinklers Are Off
One of the most important aspects of Colorado fall and winter landscape care happens after the irrigation system has been winterized.
Colorado can experience long periods of dry, mild weather during fall and winter. Trees, shrubs, and other valuable plant material still need supplemental moisture when conditions allow.
Newly planted trees and shrubs deserve particular attention because their root systems haven’t had as much time to establish. Evergreens can also be vulnerable to winter desiccation because they continue losing moisture through their foliage.
When conditions are dry, supplemental watering may be appropriate on warmer days when the soil isn’t frozen. Follow current local recommendations and consider the individual needs of your landscape rather than assuming snowfall will provide everything your plants need or, better yet, invest in winter landscape maintenance.
Use Fall to Check Your Entire Landscape
Your irrigation blowout is also a natural reminder to conduct a broader fall landscape inspection.
Take a look at mulch depths, plant health, drainage, trees, shrubs, and hardscape areas. Clear excessive debris where appropriate and identify damaged plants or irrigation components that should be addressed before spring.
This is also a good time to evaluate how efficiently your irrigation system performed during the summer. If certain areas consistently receive too much or too little water, consider improvements such as drip irrigation, more efficient sprinkler heads, or smart irrigation controls.
For homeowners interested in reducing long-term water consumption, fall is an excellent time to begin planning xeriscaping or sustainable landscape upgrades for the following growing season.
Should You DIY an Irrigation Blowout?
Some homeowners choose to winterize their own sprinkler systems, but the process requires the correct equipment and an understanding of how the irrigation system is configured.
Too little air may leave water behind. Too much pressure can damage system components. There are also safety concerns associated with compressed air.
A professional irrigation technician can properly work through the system’s individual zones, identify potential problems, and help ensure vulnerable components are prepared for winter.
For larger or more sophisticated landscapes, professional winterization is often the safer approach to protecting the irrigation investment.
Winter Watering After Your Irrigation Blowout
Winterizing your irrigation system doesn’t mean your landscape no longer needs water. Colorado’s dry winters can leave trees, shrubs, and other plants without adequate moisture, especially during extended periods with little snow or precipitation. Newly planted trees and shrubs and exposed areas can be particularly vulnerable.
During dry stretches, supplemental winter watering can help protect plant health. Water when temperatures are above freezing and the soil is not frozen, focusing on the root zones of trees and shrubs. Monitoring moisture throughout the winter can help reduce drought stress and prepare plants for healthier growth in spring.
Prepare Your Colorado Landscape for Winter with Lifescape
A successful irrigation blowout is about more than shutting down your sprinklers. It’s part of a larger seasonal strategy for protecting your landscape through Colorado’s cold, dry, and unpredictable winters.
Taking time in the fall to winterize irrigation, inspect plant health, address maintenance needs, and plan for supplemental winter watering can help reduce avoidable damage and give your landscape a healthier start when spring returns.
Lifescape Colorado provides professional property care and landscape maintenance designed around the unique needs of Denver and Front Range properties. From irrigation management and seasonal maintenance to fine gardening, enhancements, and long-term landscape care, our team helps protect the outdoor spaces you’ve invested in throughout every season.
Don’t wait for the first hard freeze to think about your irrigation system. Contact Lifescape Colorado today to discuss fall property care and prepare your landscape for the Colorado winter ahead.
