SGAFT | BY PETER KONJOIAN Sidewall winterization for small greenhouses The previous article in this series concluded that sidewall management in a small greenhouse is not a passive task once the greenhouse is operational. This article describes how a naturally ventilated greenhouse with roll up sidewalls was winterized to improve heat retention and maximize energy conservation through the heating season. My 24-by-40 research greenhouse is equipped with roll up sidewalls and ridge vent, providing yearround natural ventilation. The roll up version of a side vent was chosen over a traditional, rigid, rack and pinion design due to construction budget restrictions. By providing budget relief, the roll up version was one piece of a customized package of design features my Prospiant representative helped me create to fit my needs. Hand-cranking side vents over many years on my commercial range required up and down adjustment during the day to respond to temperature fluctuation. This time around the side vents are automated, which is particularly appreciated given the memory of manual operation. Now, side vent operation is dynamically controlled by a Bartlett Instrument Co. ClimateBoss environment control system. One side vent is shown partially open in Figure 1. THE SNOW'S RIGHT THERE The first heating season in this new greenhouse triggered a concern regarding heat retention of the singlelayer sidewall fabric. A significant winter storm's snow load slid off the roof and accumulated on the ground, pressing against the flexible fabric Figure 1. Photos courtesy of Peter Konjoian. 42 JANUARY 2025 GPNMAG.COMhttp://www.GPNMAG.COM