Many small-scale gardeners use hoop houses and high tunnel systems for producing food that they sell commercially. These structures may also be used in a garden setting if you have sufficient space. They offer numerous benefits to commercial growers and home gardeners.
So, why buy a hoop house? The most obvious benefit of owning a hoop house is that it extends the growing season. It also provides an excellent way to improve the quality of your soil and plants, as well as air quality. Hoop houses reduce energy costs and provide consumers with local sources of fresh vegetables and fruit. They can also provide home gardeners with their own fresh produce.
What is a hoop house?
A hoop house is an unheated greenhouse-type structure that is usually made by stretching plastic over a series of metal or PVC hoops to form a tunnel. However, some structure types aren’t rounded, and some have hard sides.
They don’t have foundations and are held in place by upright posits or augers that are driven into the ground. The posts need to be sufficiently strong to withstand wind and storms.
Hoop houses have different names including hoop house greenhouse, a hoop greenhouse, grow tunnel, poly-house, and polytunnel. Some larger structures include high tunnel systems.
Traditional hoop houses
Typically, hoop houses are made from steel hoops that are covered with greenhouse-grade plastic. They are sited on field or garden soil if the site is large enough, to create a growing tunnel.
The most common type is a ground-to-ground structure that creates a single bay that is 12 feet long and between 30 and 40 feet wide. Most are designed with roll-up side curtains that provide passive ventilation.
It is essential to keep the sides and end walls closed during bad weather, particularly high winds.
Rounded structures are very popular, but they tend to collect a lot more snow in winter than Gothic-type structures do. Nevertheless, according to the Cornell University College of Agriculture & Life Sciences, structures with 11-12 gauge steel arches spaced 4 feet apart will usually withstand typical snow loads.
The closer the hoops are together, the more efficiently they will bear snow loads on the plastic. Some hoop houses have straight sidewalls that add height to the structure and allow for the production of taller crops along the sides.
Gothic-style structures have also become popular. They are high tunnels with steeper peaked roofs that shed snow more effectively. A common Gothic-style tunnel size is 30 feet long by 96 feet tall.
On larger properties, farmers sometimes construct multi-bay tunnels. These are commonly large enough to accommodate tractors and tall enough to grow fruit trees.
Multi-bay tunnels are made up of multiple bays that are connected by common gutters. They are generally lower than the average hoop houses and are not designed to withstand high winds or snow loads.
Caterpillar and low tunnels
Low caterpillar tunnels are single-bay hoop houses that are usually established as temporary solutions. Most are so low you cannot stand up in them.
Low tunnels are even lower than caterpillar tunnels, usually no more than 2 feet tall. They are used inside high tunnels (see below). They protect crops that are harvested in winter or tender crops, including herbs, that are overwintered.
Benefits of owning a hoop house
A hoop house will enable you to grow several rows of crops across multiple seasons, not just the growing season. It provides protection and insulation from harsh winter conditions enabling home gardeners and small-scale farmers to increase their ability to produce food efficiently.
Hoop houses and hoop house tunnels provide a viable opportunity for greenhouse farming. They are relatively inexpensive and can be incorporated into most large gardens.
They are also versatile because, unlike structures with in-ground posts, they can be moved relatively easily. There are major benefits of this for soil health and for managing disease and reducing pests.
The Natural Resources Conservation Service of the U.S. Department of Agriculture has a high tunnel initiative for farmers who own or lease land. They offer financial and technical assistance to help producers extend growing seasons.
How do you grow plants in a hoop house?
Hoop houses are erected directly on the ground, without any form of floor. So, presuming the original field soil inside the tunnel is of good quality, all you do is prepare the soil and plant.
This is the norm, but some like to have raised beds, pots, and grow bags inside hoop houses.
There are, of course, other factors to be considered. For example, as with every other garden bed, you are going to need proper drainage.
You also need a reliable source of water throughout the seasons.
You can seed or transplant seedlings in your hoop house, just as you can in a garden bed or greenhouse. Spacing between the plants will also be similar.
The Rodale Institute, founded by J.J. Rodale, an entrepreneur from New York City, provides organic farmers with invaluable information that helps to boost productivity.
Crop management in hoop houses
Corie Pierce, who has established hoop houses in Vermont for commercial growing, shares some of her tips for laying out hoop houses. Home gardeners can use this information on a much smaller scale when planting garden beds under the protection of a hoop house.
She points out that care and maintenance needs are different from those used in open fields. For example, plants that don’t necessarily need to be staked, trellised, or pruned regularly can benefit from these strategies inside a hoop house.
Growers need to control hoop house water applications, which they do mostly with drip irrigation systems. In cold climate areas like Vermont, it’s vital to use water sparingly in winter otherwise it could end up freezing the plants.
Proper ventilation is essential to help control plant diseases that thrive in moist, warm conditions. Ventilation also allows beneficial insects and pollinators to get into hoop houses.
Something that hoop house and field cultivation have in common is crop rotation. This is extremely important to reduce the risks of pests and the many soilborne diseases that plague farmers.
The best way to control crop rotation is to have at least two tunnels, she says.
What’s the difference between a hoop house and a greenhouse?
Hoop houses perform the same basic function as greenhouses, but they are very different structures. Both are used to extend the growing season of plants.
Traditional greenhouses are considerably smaller than hoop houses. The way air is circulated is also different.
Greenhouse ventilation may be natural but it is often mechanical and created by using fans. A relatively easy way to ventilate greenhouses is to opt for structures that have side or roof vents that provide fresh, cool air.
It’s a lot easier, and cheaper, to ventilate hoop house-style greenhouse-type setups. Essentially, all you have to do is open and close the end and bottom side walls of the structure.
Also, greenhouses are usually heated artificially, which also adds expense. At the same time, you might need to use electricity to heat a hoop house too. But typically, hoop houses are not provided with supplemental heating or cooling.
Generally, it isn’t difficult to establish a suitable microclimate within hoop houses using solar energy and natural air movement.
Should I build a hoop house?
If you have the space and want to produce food, a hoop house is an ideal way to extend growing seasons. But you need to consider your site carefully.
Generally, you should avoid as much shade as possible from buildings and trees. You want as much sunlight as possible for cool-season crops and to prevent leaves from staying wet and causing foliar disease.
It is also best to choose a site with minimal exposure to the wind. At the same time, you do need breezes to maximize ventilation through the tunnel’s sidewalls.
If you don’t have the space for a hoop house in your garden, and can’t afford the luxury of a greenhouse, another option is cold frames. Cold frames are suitable for any sunny, sheltered area, even a corner of your patio.
Why buy a hoop house? As you have seen, a hoop house is an effective way of growing plants in a way that exploits the benefits of a greenhouse, with the high cost of greenhouses.
It will extend the growing season so that you can continue producing homegrown food through fall and most of, if not all, the winter months. You can use hoop houses to protect plants and their fruit from too much sun, wind, and snow.
They also offer an environment where you can control soil conditions and manage light and ventilation. Additionally, they help to improve the quality of air, which is so important for good plant quality.
Hoop houses cost a lot less than traditional greenhouses and are a lot easier to erect. You can also move them around to ensure crop rotation.
If you like the idea and have got the space, why not give hoop house gardening a try?