Photos courtesy of Atlas

Whether it’s a simple poly house or a more complex greenhouse structure, annual inspections and year-end maintenance tasks are critical. Chris Kirschner, regional sales manager at Atlas Manufacturing, describes what to look for and what to consider before the next growing season.

What are some important steps to take before buttoning up an overwintering structure?

Boots on the ground, eyes on the greenhouse! Look at your buildings with a walk around looking at the outside of the building but also inside looking out. Are there gaps around shutters or vents, doors or openings? Are there holes in your covering? Now is the time to order your poly patch tape to make any repairs. Check to make sure your poly inflation fan is working properly and order a spare. Are there places that need caulked to stop heat from leaking out or cold air from coming in? Check thermostats and heater and/or fan settings and make any necessary adjustments. This is also a great time to winterize or blow out water lines outside of the house.

What signs of wear on film determine that it’s time for a replacement?

No one really likes to fix something that’s not broke, but going into winter with covering that is marginal is not ideal. Inspect your covering closely. Overall, it may look fine, but look closely at the poly all the way around the perimeter. Everywhere the poly is held down by a fastener is a likely wear spot and could show some sings of tearing. Look closely at the poly where it crosses the structure’s framing, such as bows or purlins. Has it rubbed and turned gray? That “graying” could also be hiding small cracks or tears. Check the age of the covering. Keep updated records and consider using a Sharpie to write the install date somewhere on all your coverings. Try to use the same spot on every house if possible. A piece of poly film that looks fine but has been on for eight years needs to be replaced regardless of how it looks.

How significant is light transmission when it comes to film? How severely can the lack of light affect crops?

Light transmission is key. When trying to equate light transmission, on average, a rough idea of growth to light is equal. Therefore, just increasing your light transmission by 1-2% will give you an increase in plant growth of 1-2%. When you think of a double poly film covering having a light transmission range of 75-85% on average, discoloration or yellowing can greatly reduce this, which reduces plant growth. If you can increase plant growth by 5%, you might just pay for that new covering one year earlier.

When it comes to structures, in what instance(s) should growers not skimp on budget?

Do not skimp on loading and engineering. Never try to build a structure that doesn’t meet the snow and wind loads required for your area. You may have every intention of taking the covering off in the winter before storms, but in two or three years when the market has changed, you might need that space. If you’re going to take up precious land and put up a greenhouse, do it right and make sure that it’s versatile and will be able to react with changing markets and customer’s needs.

What are some structure upgrades that typical nursery growers should

consider? Just a few years ago, technology to remotely access and control your greenhouse was expensive and, in most cases, cost more than the average hoop house. Today that’s not the case. While you’re attending to other chores, crops, travelling, managing people or whatever your daily schedule demands, physically checking the temperature or manually turning equipment on or off just doesn’t add up. Technology now allows you to receive alerts when temps fall out of the parameters. You can adjust temperatures from your phone. You can regulate the watering or light cycle with the push of a button. Don’t get stuck in the dark ages. With automation, you’re not just saving time, you’re saving money and energy. By reading graphs and looking at your temps and energy use, you can make changes to optimize your efficiency. You’d be surprised at what little investment this can take.

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