Commercial greenhouse operators preparing for winter face more than a heating challenge. Cold weather extends equipment run times, changes ventilation needs, adds snow and ice loads and makes small envelope defects more costly. A thorough inspection before severe conditions arrive gives growers time to fix problems that could otherwise interrupt production.
The guidance emphasizes reducing downtime, protecting crop quality, managing energy use and confirming that structures and environmental systems can handle winter conditions. It is presented as a seasonal maintenance checklist rather than a single emergency procedure.
Start with the structure and envelope
Operators should walk the greenhouse inside and outside, checking framing connections, doors, vents, glazing, polyethylene coverings, seals and exterior components for damage or looseness. Weather stripping, aging seals, loose panels and gaps around openings can let air or moisture enter, increasing heat loss and complicating climate control.
For poly-covered houses, the covering should be inspected for punctures, tears, looseness and deterioration. Inflated double-poly systems also need confirmation that the inflation equipment works. Because snow and wind requirements vary by location and design, operators should maintain structural components in line with the building’s intended design and local requirements. If condition or winter loading is uncertain, the article advises involving the manufacturer or a qualified professional before a major storm.
Service heating and controls
Heating failures become more serious in cold snaps, so the entire system should be inspected and manufacturer-recommended service completed before temperatures fall. The checklist includes boilers, unit heaters, radiant systems, pumps, fans, thermostats, sensors and distribution equipment. Operators should also test circulation and horizontal airflow fans, confirm vents and louvers open and close, inspect controls, alarms and backups, check fuel supplies or delivery arrangements and review generator or emergency power procedures.
Balance ventilation, humidity and energy
Winter management is not only about adding heat. Humidity, airflow, ventilation and temperature interact, and cutting ventilation too aggressively to save heat can lead to condensation, excess humidity and uneven crop conditions. The aim is to meet crop requirements while running the greenhouse as efficiently as practical.
Efficiency checks should cover the building envelope, including doors that do not close properly, worn seals, gaps around penetrations, damaged glazing and poorly maintained vents. Retractable energy curtains or thermal screens should be inspected, including material, drive system, cables, motors, sensors and controls, so faults are corrected before nightly use. Some growers add inflated polyethylene over polycarbonate or glass sidewalls and gable ends for extra winter insulation; the article says this can reduce heat loss where suitable for the design and operation without permanently changing the glazing.
Benches, stored materials, equipment and temporary barriers should not interfere with airflow or heat distribution. A heating system can run correctly yet produce uneven temperatures if air movement is blocked. The checklist also suggests reviewing whether the greenhouse is still operated as originally designed, since production layouts, crops, benches and structures change over time.
Prepare for storms and snow
A winter plan should define who monitors snow accumulation, heating equipment, alarms, backup power and vents during storms or extreme cold. Gutters, drainage paths and areas around the greenhouse should be kept clear where practical so melting snow and ice can drain, and doors and emergency exits should remain accessible.
In snowy climates, dedicated gutter snow-melt piping can be installed beneath gutters as a separate heating zone, activated when snow or ice is present. By heating the area that needs melting directly, the system may allow energy curtains or blackout systems to stay closed instead of being opened to let greenhouse heat reach the roof and gutters. Snow removal should follow recommendations for the specific greenhouse design, because improper removal can damage coverings or structure and unnecessary activity on a loaded roof can create safety risks. Operators should know the snow and wind conditions the greenhouse was designed for and have a response plan for unusual weather.