What are the purposes of different types of polyhouse structures?
When this topic came to me I started pondering the word polyhouse. Where did it come from? Talking to a couple of old nursery people about polyhouses they came up with words like Quonset huts, cold frames, tube house and winter storage structure. I remember the term Quonset huts from days in the Army. Army Quonsets huts looked like someone cut a large culvert in half then dropped it on the ground (forget the OD (olive drab) green paint).
Introduction of poly film
The introduction of ‘poly film’ in late 60 early 70’s made it possible to build very inexpensive ‘cold frames’ or ‘winter storage facilities’ in place of the very expensive ‘glass covered greenhouse’. The poly manufacturers developed thin opac (white) plastic that resisted the sun's rays and would last the through the winter.
Why build a ‘polyhouse’?
These new structures were designed to protect container grown plants from winter winds and temperature fluctutaions. Clear plastic caused rapid and excessive temperature changes on sunny days. The opac poly film reduces the heat build up on sunny winter days.Container grown broadleaf plants, such as Hollies, Nandina, Boxwood, Camellias, Euonymus, Pieris, Abelia, etc. along with many decidous plants need some time of winter protection
What type of overwintering structure works best?
One of the first polyhouses I remember seeing was about 4’ tall it was made by curving a 10’ x 1” piece of conduit then placing the conduit onto re-bar stakes. After filling it with plants, white plastic was rolled over the frame and weigthed down on the edge with sand. There was no way to work in these structures until being uncovered in the spring. This structure works in cold areas since they remain sealed all winter.
Today the structures are made with the idea of entering during the winter to work on the plants. The height and width are detemined by what plants go in, how you move plants in and out, and how you will vent the structure. The structure can be a wood a-frame, a metal arch using whatever pipe or tubing you can find. Even hog fences will work. Choose a material that can support your average snow load and more.
Where to go for help on 'ployhouse' construction?
Visit the best wholesale plant grower in the Midwest for ideas on ‘ployhouse’ structures. We have over 90 years experience in building polyhouses year after year and have learned a lot by trial and error which has resulted in a pretty good product.