Producers and the U.S. Department of Agriculture show a great deal of interest in high tunnel farming, growing vegetables or floriculture in new high tunnel structures USDA has even has offered robust funding programs to support the technology in recent years.
While production farmers would mostly scoff at the idea of growing crops inside a structure, applications for high tunnel farming seem to be increasing, with even a few production farms putting in test tunnels to check the water and cash in on farm-to-table marketing. Most high tunnel farming operations so far, however, are limited to small farms and independent or sustainable growers.
How does high tunnel farming differ from standard greenhouse farming operations?
Often called a poly-tunnel or hoop house, a seasonal high tunnel is basically a greenhouse without the controlled-environment equipment—heaters, large fans or humidity control devices that allow for year-round farming. Unlike greenhouses, they are constructed of lighter material, are rather easy to construct or assemble and to move if the need rises.
A hoop house is technically a tunnel made of polyethylene, usually semi-circular, square or elongated in shape. The interior heats up because incoming solar radiation from the sun warms plants, soil, and other things inside the building faster than heat can escape. Air warmed by the heat from hot interior surfaces is retained in the building by the roof and wall.
The advantages to growing inside a high tunnel are many, not the least of which is a longer growing season that gets a jump on most spring crops and extends the fall growing season until the heart of the winter season.
Another advantage is that a tunnel provides a level of protection against problems associated with pests and diseases.
