High or low tunnels, greenhouses or garages—hoop houses are handy structures on hobby farms.
Photo courtesy Four Season Tools
All hoop houses have steel, PVC or poly-pipe "hoops" that support a flexible cover. |
I
just built my first hoop house. OK, it isn’t what you might think of
when you think hoop house; it’s really what’s called a low tunnel. In my
case, I bent steel electrical conduit using a hoop bender from Lost
Creek Greenhouse Systems. However, in all respects, my 4-foot wide,
4-foot high, Agribon-fabric-covered structure is as much a hoop house as
a 30-foot wide, plastic- covered greenhouse or fabric-tension garage.
What
all of these structures have in common is simplicity of design that
uses steel, PVC or poly-pipe to create half-circle or “hoop” supports
for a flexible cover. How the hoops are fixed in place and how the cover
is secured are all that really differs. Whether covered with plastic or
heavy-duty woven fabric, properly tightened and anchored, a hoop house
can withstand high winds and a heavy snow load. The hoops themselves can
vary from PVC pipe to steel electrical conduit to a range of steel and
wood components. Using wood, concrete, gravel or earthen pads, the
structures are fast to erect and low in cost compared even to pole
barns.
Photo courtesy Farmtek
Hoop houses are particularly valued for their year-round food-production capabilities. |
Hoop
houses have already earned a home on many small, hobby and large,
commercial farms alike for crop storage, livestock shelter and equipment
storage. Hoop-house designs are particularly appealing for year-round
food production.
“In my opinion, the hoop house is the No. 1
technology for market and home gardeners, and interest in them is
exploding,” says Steve Upson, horticultural consultant for The Samuel
Roberts Noble Foundation, a nonprofit agricultural research
organization. Since 1995, Upson has been working with, improving on and
spreading the word about hoop houses: “They aren’t new, but they are
being adopted today at a phenomenal rate. Their use cuts across
philosophies of growing, regardless of what inputs you use for managing
fertility or disease. Everyone can use hoop houses.”
Year-round gardening expert Eliot Coleman agrees wholeheartedly. He’s
been using stationary hoop houses for years to extend his market-garden
production and sales season. His high tunnels, when used in conjunction
with low tunnels inside, extend his normally short, Maine-seacoast
growing season into a year-long endeavor without the need for additional
heat production.
“High
tunnels have the effect of moving the plants about one and a half [USDA
hardiness] zones or 500 miles south,” he says. “Put low tunnels covered
with Reemay [polyester fabric] over the plants inside the high tunnels,
and we’ve moved the plants another 500 miles south.”
Coleman
has modified the concept by placing interior bracing on the hoops, as
well as skids or wheels on their bases, to create a movable high tunnel
that he can place over an early planting of warm-season crops, like
tomatoes, that would normally struggle to mature in the cool Maine
summer. As they finish production in mid-October, Coleman moves the hoop
house over an August-planted cool-season crop to protect it through the
late fall and early winter. As those crops are harvested, beds are
replanted with late-winter and early spring cool-season crops. As they
mature, the hoop house is again moved to receive summer-crop
transplants. The benefits of this system include the ability to rotate
in-ground beds for disease control and fertility.
“The real
benefit of these movable high tunnels is the flexibility,” says Greg
Garbos, president of Four Season Tools. “They just make greenhouse
production a different game altogether.”
Garbos has worked with
Coleman to commercialize and market the movable hoop-house design. “To
be movable, they have to be really rugged and structurally sound,” he
explains. “As the unit is moving, you don’t want it to twist, so we add
more braces than in a typical high tunnel.”
Introduced in 2009, the structures are available in a 16- by 24-foot
gardener size and larger sizes for market growers. They’re catching on
fast, and not just for vegetables. Jeff Bahnck and his wife, Alethea, of
Bridport, Vt., have modified a 20- by 48-foot Four Season Tools movable
high tunnel for their 500 laying hens. Bahnck built and installed
laying boxes, roosts, feeders and waterers—all hung from the hoops and
braces of the high tunnel. In the summer, shade cloth over the top and
galvanized mesh on the sides protects the hens from predators of all
kinds. In the winter, clear poly provides plenty of light and keeps the
temperature above freezing. Special bases allow Bahnck to move the high
tunnel coop laterally as well as forward and back across the field.
“As
soon as the chickens hear the tractor, they all run to the side [of the
hoop house] where it is, as they know they are moving to fresh
pasture,” he explains.
Bahnck is working on special caster
wheels that will make lateral moves easier. Meanwhile, Garbos is
developing a turnkey, high-tunnel, Hoop Coop kit with bracing for
lateral moves, a watering system and plans for wooden components.
Photo courtesy Four Season Tools
The Bahncks modified a hoop house to act as a chicken tractor by suspending feeders and waterers from the structure's supports. |
Tod
Hanley and his wife, Jamie, can’t move any of their high-tunnel hoop
houses with a tractor, but they can take down any one of their five 17-
by 100-foot structures and re-erect it in about 21⁄2 hours in calm
weather conditions. Hanley designed a quick-anchor system using rebar
driven into the ground. The hoop ends simply slide over the portion of
the rebar sticking out of the ground. Tensioning ropes attach to links
on the rebar. Hanley designed a hoop bender that cuts his hoop costs in
half and lets him use square steel tubing instead of the more common
round steel or electric conduit.
“We’ve tried different types
of plastic and also shade cloth to cool the temperature down in the
summer, something that is needed for vegetable production during
Oklahoma summers,” he says.
Hanley uses off-the-shelf
components to construct his high tunnels. Many of the components come
from FarmTek. Barry Goldsher, president of FarmTek, says both the demand
for hoop buildings and the options available have grown tremendously.
“The
variety of hoop houses and coverings is unbelievable,” says Goldsher.
“But with smaller structures, many of the components are the same,
whether covered with greenhouse film or fabric. Our customers use them
for everything from greenhouses to aquaculture and even as solar-powered
kilns for drying wood.”
He advises anyone thinking about buying
a hoop house to consider the end use in evaluating the construction
materials, whether fabricating the structure yourself or buying a
turnkey kit. He notes that high humidity can quickly rust poor-quality
steel, even if it’s powder coated. Some steel products, including
FarmTek’s Allied Gatorshield structural steel tubing, are galvanized
inside and outside to prevent rusting or corrosion.
“To build a
structure that will last, you need the right diameter pipes [hoops] and
rafters, purlins, connectors and anchors,” says Goldsher. “The cover
needs to be attached correctly so it doesn’t blow away or tear. It has
to be tight. You can always buy something cheaper, but it doesn’t really
pay.”
About the Author: Jim Ruen lives, writes and works with his gardens and tree farm in the Bluff Country of southeastern Minnesota.T
his article first appeared in the January/February 2010 Hobby Farms
.
