How to Winterize a Drip Irrigation System: 5 Steps to Success
Add “winterize the drip irrigation system” to your to-do list
- Protective eyewear
- Protective gloves
- Air compressor (optional)
If you use one in your garden, you know that a drip irrigation system helps conserve water, fight off weeds and plant diseases, and minimize the time you spend on yard work. It’s crucial to learn how to winterize your drip irrigation system every year before cold weather arrives—ideally at least two to three weeks before the first frost. Otherwise, any water remaining in the system will freeze and expand inside, damaging the tubing, valves, and other accessories.
Luckily, winterizing your drip system is a quick and simple process, whether you use a manual or automatic drainage system. Follow these steps to protect your irrigation equipment from the looming freezing temperatures and ensure that it stays ready to get back to work at the first sign of warmer weather next year.
Preparing to Winterize Drip Irrigation System
As the weather cools off, trim any annual plants and clean up perennials. Cover plants that may be susceptible to early frosts and need a slower introduction to winter. When you’re ready, shut off your irrigation system, ideally in October to avoid the worst of the freezing weather. You don’t need any specialized gear for these steps, but we do suggest grabbing a pair of outdoor work gloves if you have them.
How to Winterize Drip Irrigation
Follow these steps to winterize your drip irrigation system like a pro.
Turn Off the Main Water Supply
Turn the master shutoff valve on your mainline to stop the flow of water to your system.
Remove the Faucet Assembly
Take apart the head assembly. Confirm there isn’t water remaining in the backflow preventer, the filter, and the pressure regulator. If you have a timer, remove the batteries to prevent corrosion. Once complete, pack and store these components indoors, where they’ll be less likely to freeze.
Some drip systems use outdoor hoses connected to faucets to work. If you have this type of system, unscrew the hose and make sure it’s drained of water. Store the hose away from freezing conditions until winter is over.
Drain the Lines
If you have a manual drain system, open the end caps on all the emitters and let the water drain out. Walk through the whole system, lifting the tubing and the fittings at any low points to flush out any trapped water.
If your type of system features automatic valves, manually confirm that all valves are open and then run the controller through its normal cycle to remove any remaining water. Re-open all valves to prevent water from gathering inside while it sits idle.
Blow Out With Compressed Air
Drip irrigation isn’t under the same pressure as a sprinkler system, and water is less likely to linger in delicate components that it can damage when frozen. That’s why it’s a largely optional step for most home drip systems. However, if your irrigation system combines drip lines and sprinklers, we highly recommend a blowout. It’s also a good idea if your manual drip lines are sloped in a way that makes gravity-based drainage difficult.
If you don’t have experience using an air compressor, consider hiring a sprinkler winterization pro to complete this task. Highly pressurized air can easily cause serious injury. If this is a task you’d prefer to DIY, rent an air compressor from your local equipment lender or hardware store. Wear ANSI-rated eye protection to shield yourself from the pressurized air and any debris it may set loose.
Slowly turn the shutoff valve back to the open position. Attach the compressor hose to the threaded opening on the mainline and ensure the connection is tight; use pliers or a wrench if necessary. Set the air compressor to 30 pounds per square inch (psi). Slowly increase the pressure as needed and stop once air comes out of the emitters.
Cap the Adapter and Tubing Ends
Photo: Ofresia / Adobe StockOnce the lines have fully drained, put all the end caps back on the emitters, but leave them loose—this will allow any excess water to drain throughout the winter while preventing wandering insects from damaging the tubing. Just don’t forget to tighten the end caps before you start the system up again next spring. Lastly, cap the female end of the threaded swivel adapter removed from the faucet assembly during step two.
DIY vs. Hiring a Pro
If the idea of tackling yet another annual yard chore is overwhelming, you can turn to the pros to keep your drip irrigation system safe throughout the cold months. Enlist the help of a sprinkler winterization pro to address any repair needs and prepare your yard for the planting season next spring.
Professional landscapers will bring their own air compressors and can easily blow out irrigation systems, which is an important step if you have a large or sloped system. For this reason, in colder climates it can be a good idea to hire a pro if you can’t get your hands on an air compressor. For smaller systems and milder climates, especially if your irrigation is drip-only, DIY draining will suffice.
If you spot a few garden or yard plants that need watering before the start of spring, you can irrigate them with care. Attach a garden hose and use it to directly spray your plants. However, do not connect your drip irrigation system until the last of the expected freezing weather has gone.
Not usually. It’s very important that you clean the irrigation filter out, but they last for several years. However, if you notice that your system keeps getting clogs, you may want to purchase a finer-mesh filter, and set a cleaning schedule so it’s always free of debris.
You may have to dig out drain valves if they are buried under dirt. This method isn’t ideal, and it increases the chance of clogs and damage. Ideally, a drip irrigation system buries drain valves in a gravel pocket so they are easier to access and better-protected. If you have trouble accessing drain valves, hire a sprinkler professional to find them safely and efficiently.
If your irrigation system is not working properly after winterizing it, your emitters probably clogged over winter. This issue is fairly common, especially if your area received heavy snow and precipitation that winter. You may need to go through your drip lines and clear your emitters to get your system back to the state it was before. Additionally, if your drip irrigation uses batteries to power local timers, check that the timers still have power and replace the batteries if you need to.
