MSU Extension

Many Michigan schools have joined in on the local food movement by purchasing a hoop house or high tunnel in recent years. Students across the state are learning valuable plant biology, ecology, agronomy and other STEM knowledge and skills in these structures, which are designed to lengthen the growing season. However, like all structures, hoop houses and high tunnels require maintenance and sometimes they become damaged by wind, rain, snow, ice, trees, and even vandalism.

Collin Thompson, Farm Manager and Program Instructor with Michigan State University’s Upper Peninsula Research and Extension Center, has been building and growing in hoop houses and high tunnels for the past six years. If the hoop house or high tunnel at your school is damaged, here is some advice from Thompson for how to evaluate and repair the damage so your students can continue to gain valuable lessons and experiences from these unique structures:

1. Assess the extent of the damage. The plastic covering the structure is usually the first thing to give out. This is a common issue and replacing plastic can be done relatively simply. However, you need to look carefully at the frame. Are any of the hoops or metal pieces bent? Can you move pieces that should not move? Does the door open and close properly? Are any screws or bolts missing? Are there gaps around the door? Be sure to look at the undamaged areas closely and compare them with the damaged areas.
2. Take detailed photographs and measurements. You will need to know how wide, long, and high (at the highest point) your hoop house or high tunnel is. You will want several photographs of the damaged areas from many different angles so you can communicate via email with a vendor. There are many different names for the same parts so having photographs to send is really the best way.
3. After you have an inventory of the damage, work with your school’s accounting and purchasing experts to contact the vendor you purchased your hoop house or high tunnel from and see if any parts are under warranty. Thompson says it is very rare to have an entire structure under warranty, but there may be parts that are. The company that sold you the hoop house/high tunnel may have to work with the part manufacturer to get the part under warranty replaced, so this can take some time. Thompson says in his experience, repairing a hoop house/high tunnel structure is usually cheaper than replacing it.
4. If you can’t find the company you purchased the structure from, you might want to seek out the help of a local farmer that uses hoop houses/high tunnels and see what company they use. You can also find Michigan-based hoop house and high tunnel sales and installation companies online. Having a technician from a company that did not sell you your structure come to your school can be expensive, so be sure to know what the service charge will be before you place your order.
5. If the plastic has rips or tears in it, you might be able to fix them with a product called poly-patch tape. Thompson recommends applying the tape generously on the inside and outside of the tear. He says even large holes can be repaired this way. If you need to replace the plastic, you will need to measure the length and width of the current piece. You can do this by using a rope to go over the top of the structure and then measuring the rope or using a flexible measuring tape.
6.  If you decide to replace your plastic, Thompson says the best time to do this is on a hot day so the plastic will stretch more easily and will fit tight on your structure. Pulling plastic in the winter is not advisable because the plastic is cold, which means it will shrink and then it will be loose fitting during the hot months. Replacing plastic can usually be done in one day and can be a valuable experience for students.

Michigan State University Extension’s Community Food System Work Team supports efforts to grow the local food system, which includes school-based gardens and hoop houses/high tunnels. Sign up for our Community Food System free e-newsletter online.