We all have our winter routines. Some people look forward to fishing out the Christmas decorations from the attic to put up around the house. Others cherish dressing up in mittens and knit caps to go play outside during the first snowfall. Or perhaps you prefer warm winter nights curled up by a fire, sipping hot cocoa.

Whatever your personal rituals, an important part of your autumn routine as a landscape professional should include preparing your clients’ irrigation systems for the cold months ahead. This is a crucial annual task that should be completed on every system in colder parts of the country.

With luck, it’s something your customers will ask you to perform. But you may have to educate them on winterization if they aren’t familiar with the process. Once they realize the importance of this service, it’s one you can bundle into a year-long contract. Many contractors often place winterization in an annual contract that also includes spring activation and backflow tests.

“We send out our agreements in the fall,” said Tony Dilluvio, managing partner of Aqua Turf Irrigation Systems, LLC, which operates in New York, New Jersey and Connecticut. “That agreement typically covers fall winterization and the subsequent spring startup.” Aqua Turf will sell the services separately, but provides a discount if the customer signs up for both.

In addition to being a much needed service, it generates a great revenue stream for you. There are several benefits to winterizing your clients’ irrigation systems. Keeping the irrigation system running during the winter is a waste of water; more importantly, if the system runs, that water can end up freezing on sidewalks and roads, creating hazardous conditions.

However, the main reason to winterize is that frozen water can cause serious damage to your client’s irrigation system. Water expands as it freezes, which can severely damage pipes, fittings, backflow devices and sprinkler heads. PVC pipes are especially susceptible to damage. This can lead to costly repairs or even a replacement of the entire system. You have to go beyond just shutting the water off.

Even a little bit of water left in the pipes can cause a lot of damage. Ryan Jardine, president of Quality Irrigation in Omaha, Nebraska, often sees damage to irrigation systems caused by do-it-yourselfers. “The homeowners won’t get all of the water out and they’ll leave it that way,” he said. “In the spring, you’ll show them freeze damage. When ice breeches the pipe, it spiral cracks it.”

Dilluvio sees the same thing. “We have to fix systems that weren’t blown out properly because the gardener or a friend did it and they didn’t have a big enough compressor or didn’t run it for a long enough time,” he said. “Maybe they didn’t go through the zones from the highest elevation to the lowest elevation. There are a few little tricks of the trade that the gardener or friend don’t know how to do.”

Speaking of damaged equipment, this can be a great time to check your customers’ systems and recommend needed maintenance or repairs. Before starting the winterization process, you can make note of any damaged sprinkler heads or pipes that will need to be replaced. It’s a good opportunity to check for any pressing problems, as well as to alert your customers to work they’ll need down the line. “We’ll put a note in the file and the repairs are usually addressed in the spring,” said Jardine.

To start the winterizing process, you must first shut off the main water valve. On larger commercial properties, this may require the assistance of a facilities manager or groundsperson.

It’s helpful to make a note of what’s required to toggle the main valve on and off in your clients’ records to speed up turning the water back on in the spring.

You can use the automatic or manual drain valves to clear out the piping network. Most homes have a drain valve in the basement or crawlspace. But simply draining the system this way will not ensure that all of the water is cleared out. That’s why the standard procedure is to blow out the system with compressed air, to be sure no water remains.

There are other things to keep in mind before you begin. One is that you want to make sure the air lines you use are professionallycrimped. It may be tempting to save money by using screw clamps you attach yourself, but it isn’t worth the risk.

“A lot of guys will use screw clamps and they’ll try to assemble the air hose themselves,” said Jardine. “If that clamp comes loose, that air hose is just like what you see in the movies —flipping around uncontrollably. It can break windows; you can severely harm yourself.”

Jardine also warns that it’s best to run the air line through unoccupied spaces. You don’t want the line running through the interior of someone’s house or through a commercial office where employees are present.

“You don’t want to drag an air line through an occupied building,” Jardine said. “If that comes loose, it can damage a ton of stuff. If you are winterizing a commercial building, you want to insist that they have an access point sprinkler system on the outside of the building. You never want to take a hose inside a building.”

Next, attach an air compressor hose to the fitting. The compressor valve should be closed when attaching. You’ll need an industrial-grade compressor. Commercially-available compressors don’t generate enough air pressure to clear all of the water out of the pipes. If you don’t own an industrial compressor, they can be rented.

But while you need a powerful compressor to blow out all of the air, you’ll want to make sure not to put too much pressure on the system.

“You can actually damage an irrigation system with high pressure; you can blow the heads out of the ground or break the pipe,” warned Dilluvio.

The industrial compressors Aqua Turf uses have an absolute pressure of about 120 to 130 pounds per square inch (psi). But his workers only send around 65 to 70 psi through the pipes on most sites. “There’s usually a Y-valve on there,” Dilluvio said. “So my guys will open up the valve, then open up the Y-valve to bleed off the pressure.”

If the system has a flow sensor, you want to remove it before you begin. You also want to make sure the isolation ball valves on your backflow device are closed. The drain to the home’s basement should also be closed during this step. Failure to perform any of these steps can cause severe damage.

“When you hook up air to the house, don’t open the drain to the basement,” said Jardine. “If you hook up the air on the wrong side of the backflow and you open the drain in the basement before you open the air, that compressor is going to take that water and push it out extremely fast. You’re going to potentially have water spraying out like a broken fire hydrant in the basement.”

After checking the backflow device, you can open the compressor valve. Starting with the area furthest from you, or highest in elevation, pump air through each zone. You should run air for about two minutes per zone. Watch the sprinkler head to make sure water is still coming out. Once all of the water is purged, you’ll get a mist coming out instead of a steady flow. That’s the signal that you’re ready to move to the next zone.

Keep a close eye on those sprinkler heads. Running the compressed air for a long time after all of the water has been cleared can also cause damage. Once the pipes are dry, the air flowing through creates friction. That friction can heat up the pipes, melting interior components.

“There’s always heat involved with the compressed air,” said Dilluvio. “A lot of Company times, if you don’t know what you’re doing, you can run much hotter air than the components can tolerate and you can melt them.”

Once you’ve hit all of the pipes and sprinkler heads, disconnect the compressor and release any built up air pressure. Now you’re almost finished, but not quite. There’s water left inside your backflow device, which was trapped in there when you closed the isolation ball valve.

Manually open the isolation ball valves to release the built-up water. Once drained, leave the valves halfway open. The test cocks should also be left open. Some contractors go the extra step of removing the backflow device completely by uncoupling either side, but this is optional.

Finally, you should check the control system. Even with no water flowing through the system, if left on, the solenoids in the valves or sprinkler heads will dry-fire all winter.

While you do want to shut the system down, you don’t want to power the controller off completely. If you do, condensation can collect inside the unit. This can damage the electrical components. Instead, keep the power supply on and the dial set to the off position.

Once you learn the steps involved, winterization becomes an easy process that can be done in as little as 15 minutes on standard residential properties. One of the biggest challenges can actually be manpower to meet having enough your area’s need for this service. “The window of time is pretty short,” said Jardine. “Usually, it’s just the month of October, and maybe a little bit into November. The hardest thing when you’re growing your business is that the more customers you get, the more employees you need to provide service within that window.”

You can also use winterizing the irrigation system as an opportunity to conduct other annual maintenance. For example, while onsite to winterize, it’s a great time to add mulch to beds and planters, aerate turf or prepare plants and trees for their dormant winter phases.

Both Dilluvio and Jardine estimate that their companies will handle about 3,000 winterization jobs.

To help manage the demand, Jardine automatically sets aside appointments for clients who have had winterization done in the past.

Since his company services three states, Dilluvio has learned another trick to make things more efficient. “We designate certain days for certain geographical areas,” said Dilluvio. “We’re not spending a lot of time traveling from one house to the next. We’re grabbing a bunch in one neighborhood.”

Even with this geographic efficiency, Aqua Turf expands its hours in the winter months in order to get to everyone. “We expand the work week to include Saturdays and Sundays, with longer hours during the day,” Dilluvio said. It can still be tricky, though, since there are fewer hours of daylight in the winter months.

Another challenge is to make sure that you have the proper license to perform winterization services. This licensing may vary from region to region. “In our market, you have to be a licensed sprinkler contractor,” said Jardine. “So, not all landscape professionals can provide the service.”

Winterization is vital for protecting your customers’ equipment in the frosty winter months. However, it’s also a fairly straightforward and simple process to master. It can provide you with a chance to look over a client’s irrigation equipment and have it ready for the spring. Make this service a part of your winter routine and your clients, and your wallet, will thank you.