Winter Harvest



Many growers struggle to weigh the advantages and disadvantages of year round greenhouse growing. Some people prefer to harvest as many times as they can during the spring, summer and early fall only. But for those who want to go the extra mile, a winter harvest might offer the rewards you are looking for despite any additional challenges.

Many growers choose to use the winter months for a break after a hard year’s work and to avoid some of the struggles of flowering during the winter months. Others use the winter months to vegetate their plants because during that phase the plants are not as sensitive to mold as those that are actively flowering. The first flowering run is saved for early spring, when environmental conditions improve. However, a winter harvest is still possible with the right equipment.

Beyond the obvious pitfall of shorter days and the need for supplemental lighting, heating and humidity become the main challenges. These issues can be fixed with a variety of solutions, depending on the permanence of your structure. The two most popular heating options are propane heating and radiant (geothermal) heating.


Propane heating offers a way to safely heat your greenhouse while resolving humidity issues slightly. Such a large influx of dry heat from the propane system will offset the natural humidity of the winter season. Keep in mind the inherent cost of propane when choosing your heating method. The warmer you must keep your greenhouse, the more money it will cost.


Geothermal heating requires more effort to setup, but to growers who use it, the benefits far outweigh the initial costs. Low-grade geothermal heating relies on the Earth’s internal temperature to heat or cool the greenhouse air. By burying yards of tubing well below the frost line under your greenhouse, cold air that is forced through the system is warmed by the heat of the Earth itself. The depth of the frost line, under which the soil remains at a constant temperature, varies based on location. Be sure to check on proper positioning before beginning to dig. Cost of this system is determined only by setup and maintenance. Using the system costs nothing, hence its popularity among established growers.

Additionally lots of winter growers (even those just vegetating during the winter) will choose to use a double layer of poly with an inflation blower to create a bubble of air for insulation. This can help reduce energy costs by as much as 30%.

Even considering all these potential issues facing a winter harvest, many people decide that the increased production is worth it. When growing year round, you will constantly be growing, flowering, or harvesting. Having a constant supply for your farm and avoiding the glut of the regular season has its obvious benefits.


When using our auto blackout light deprivation system, paired with our recommended equipment, many of the winter growing issues can be avoided. An automated controller can automatically raise and lower blackout poly, open and close louvers with the built-in thermostat and control ventilation operations as well as heaters. Consider upgrading to our automated system or having us retrofit your existing system in order to streamline your production and minimize your workload.

For more information on how to make your grow site produce to its full potential, check out our Winter Growing FAQ or call our sales team for more information on winter growing accessories.