Property Winterization and End-of-Season Shutdown SOP

Purpose

Define the standard end-of-season winterization procedure for a residential or light commercial property. Winterization is one of the highest-margin single visits of the year for a lawn-care business because it bundles services the customer cannot easily perform themselves (irrigation blow-out, final mow, equipment storage prep) into a discrete deliverable with a flat price. It's also the visit that protects the property over the winter so the spring startup goes smoothly - a poorly winterized irrigation system creates expensive freeze-damage callbacks the following spring.

Scope

Applies to:

• Properties in regions with hard freeze (sustained temperatures below 28 °F)
• Properties with in-ground irrigation systems
• Properties with annual flower beds, shrub plantings, or trees needing winter preparation
• Commercial accounts with hardscape and outdoor water features

Excludes:

• Properties in non-freezing regions (winterization there is a different service)
• Properties without irrigation (only final mow and cleanup applies)
• Pool / spa winterization (separate trade)

Responsibilities

• Lead technician runs the winterization checklist
• Helper / assistant handles equipment operation, blowing, bagging
• Office schedules winterization visits across the customer base before first hard freeze
• Customer is notified in advance to ensure access (gates unlocked, pets secured, water on at the spigot)

Timing

The single biggest scheduling consideration in winterization is the first hard freeze. Schedule:

• Cool-season regions (Pacific Northwest, Northeast, Midwest): late October through mid-November
• Transition zones (mid-Atlantic, southern Midwest): early to mid-November
• Mild winter regions with occasional freezes (southern US, coastal): on-demand before predicted freeze events

A surprise early-season freeze before the irrigation is winterized creates a 6-figure callback exposure across a typical 200-account portfolio. Watch the 14-day forecast in October and accelerate the schedule if needed.

Procedure

Step 1: Final mowing

1. Cut at the standard height for the grass type (cool-season usually NOT lowered for winter - keep at 3 inches for cool-season for winter protection)
2. Bag clippings on the last mow even if the customer's program normally mulches
3. Trim and edge as usual
4. Blow off all hardscape

Step 2: Final leaf cleanup

If leaves are still falling, schedule a final leaf cleanup visit AFTER most leaves are down:

1. Mow with mulching attachment or bag
2. Blow leaves from beds and corners
3. Final blow-off of hardscape

Step 3: Irrigation system blow-out

This is the critical step. Water remaining in irrigation lines expands when frozen, cracks PVC and brass components, and creates spring repair bills that exceed the winterization fee many times over.

1. Locate the main shutoff valve to the irrigation system (typically inside the house OR in a valve box near the meter)
2. Close the main shutoff
3. Open the test valves at the system controller manifold
4. Connect an air compressor to the system blow-out fitting (typically a quick-connect on the manifold downstream of the backflow preventer)
5. Set the compressor pressure regulator to 40-60 PSI for poly pipe systems, lower (30-40 PSI) for systems with above-grade brass
6. Activate zones one at a time from the controller
7. Run each zone for 2-5 minutes OR until the heads are blowing dry air with no water mist
8. Repeat for every zone in the system, working from furthest from the compressor to closest
9. Close the test valves on the manifold after the last zone
10. Drain and remove the backflow preventer per its winterization procedure (often required to be removed entirely in freeze zones)

Common pitfalls:

• Pressure too high blows seats out of valves and ruins drip components
• Running a zone too long with no water heats the heads and damages internal seals
• Forgetting an isolated zone (drip line on a separate zone valve) leaves water in that line to freeze

Step 4: Backflow preventer service

Most jurisdictions require an annual backflow test (separate from winterization). Some require the device be drained and removed for winter; others require insulating covers.

1. Drain the backflow preventer per its manufacturer's specification
2. If removal is required: cap the lines, store the device indoors, tag for spring reinstallation
3. If insulation covering is the option: install a foam insulation cover before first freeze
4. Document the procedure performed for the customer file and for the spring activation visit

Step 5: Outdoor faucet (hose bib) protection

1. Drain each outdoor faucet by opening the spigot fully and disconnecting hoses
2. If the spigot is a freeze-proof style with the shutoff back inside the heated wall: drain only, no further protection needed
3. If the spigot is an older type with the shutoff outside the wall: shut off the supply inside, drain the spigot, install an insulating cover
4. Disconnect and drain all garden hoses; store coiled and indoors if practical

Step 6: Annual flower bed cleanup

1. Remove annual plants that won't survive winter (impatiens, petunias, marigolds, etc.)
2. Cut back perennials to 4-6 inches above ground (some perennials are exceptions - verify before cutting)
3. Apply winter mulch over root zones at 2-3 inches depth
4. Bag or compost the removed plant material

Step 7: Shrub and ornamental tree protection

For cold-sensitive plantings:

1. Wrap young or borderline-hardy trees with tree wrap to prevent winter sunscald
2. Build burlap windbreaks around exposed evergreens
3. Apply anti-desiccant spray (Wilt-Pruf or equivalent) to broadleaf evergreens to reduce winter water loss
4. Cage vulnerable shrubs with burlap or wire to protect from deer browse

Step 8: Hardscape and outdoor features

1. Clean and store patio furniture if customer hasn't already
2. Drain and store decorative water features
3. Cover or store outdoor grills
4. Apply ice-melt-resistant sealant to vulnerable hardscape (recommendation only; sealant work is usually a separate paving service)

Step 9: Equipment storage prep (if servicing customer-owned equipment)

Some lawn-care companies offer end-of-season storage prep for customer-owned mowers and other equipment as an add-on:

1. Drain fuel from gas equipment OR add fuel stabilizer
2. Change engine oil
3. Sharpen mower blades (winter storage is the best time)
4. Lubricate moving parts
5. Store in a clean, dry location

This is upsold to customers who would otherwise face spring equipment failures.

Step 10: Documentation and customer handoff

References

• ASABE (American Society of Agricultural and Biological Engineers) irrigation standards
• IA (Irrigation Association) Best Management Practices for Irrigation Winterization
• IPC (International Plumbing Code) backflow prevention requirements
• IRC R310 (residential plumbing winterization principles)
• State backflow testing and registration programs
• Manuall internal: Spring Lawn Startup SOP, Fall Aeration and Overseed SOP, Backflow Prevention Reference