It appears that the probability of getting an accumulation of snow and/or ice over the weekend is real. We are rapidly approaching greenhouse transplant production and this storm could negatively impact greenhouses. It has been several years since we have encountered this type of event and I wanted to provide some reminders in terms of preventative steps and things to consider.
- Turn the heaters on and keep them going during the event to minimize roof accumulation of any snow or ice. The weight can become excessive with just a few inches of wet snow and fractions of an inch of ice. Set the heater thermostat to 60 degrees Fahrenheit or higher, if needed, to ensure adequate melting. Ensure greenhouse heaters are working and the fuel tanks are adequately filled. They may have to run continuously for a couple of days and it will get costly in terms of fuel usage, but it is better than replacing a house this close to seeding. Inflation fans should stay on to keep the plastic tight and make it easier for any accumulation to slide off the roof and provide additional insulation. It is a good idea to go ahead and get the greenhouse temperature elevated prior to any frozen precipitation. Heaters may have a hard time keeping up with the accumulation if the precipitation rate is excessive and they wait until the precip begins. Continuous monitoring will be important.
- With a significant ice accumulation event, there could be a lot of widespread power outages. Many growers today have backup generator capacity, but you need to ensure all equipment is functional and enough fuel is available to operate a stand alone generator or tractor driven PTO unit for multiple days. The goal is to keep the heaters and inflation fan operating during the event.
- If you do not have backup power and experience a power outage, it might be safer to remove the plastic or cut it to avoid any significant structural damage to the greenhouse. Structural damage would be more expensive and timely to replace. Otherwise you will need to manually remove any roof accumulation from the inside of the house and without the inflation fan operating. This will be more difficult to complete due to the sagging plastic between the roof supports and require continuous monitoring.
Most growers have dealt with these types of winter events in the past, but once again it has probably been several years since the last. We are a few days out and things could improve, but it is better to be prepared for the worse and hope for the best.
