Year-round harvest of Michigan crops happening at MSU hoophouses

MSU professor talks about the value of extending Michigan's growing season

Hoophouses help farmers extend the growing season.

As spring begins to settle in, many Michiganders eagerly anticipate the return of locally grown fruits and vegetables. What many may not realize is that fresh produce has been available all winter at the Michigan State University (MSU) Student Organic Farm (SOF).

Hoophouses – unheated greenhouses made of steel frames covered in plastic film – enable the SOF to offer fresh produce year round. Inside the structures, also called high tunnels, farmers are able to extend the growing season for many crops such as tomatoes, peppers and flowers, which typically grow during the summer. The harvest of crops such as lettuce, kale and carrots in the winter is also commonplace.    

Although the SOF has been around since 2002, AgBioResearch horticulturist and SOF coordinator John Biernbaum said the biggest challenge is not growing the crops during Michigan winters but making people aware that it is possible.

“I’m convinced that some people who tour the facilities in January and February think we’re hiding heaters somewhere in here,” he joked.

“People come to the Student Organic Farm for tours, courses, workshops and volunteer opportunities, and when we demonstrate the idea of ‘season extension,’ it’s fairly easy for people to get,” Biernbaum said. “But the idea of ‘winter harvesting,’ which we’ve been doing for 10 years, has been much harder for some to embrace.”

But it’s not just the perceived implausibility of harvesting vegetables in the cold, blustery months that has made the growing technique slow to catch on.

“Traditionally, specialty crop farmers work long hours in the summer and use the winter for some down time,” Biernbaum said. “Hoophouses enable some farmers to grow less strenuously in the summer and spread the work out more evenly throughout the entire year. An added benefit is that farmers have less competition selling produce in the winter and, therefore, would not be competing to sell vegetables at summer farmers’ markets when supply is higher and prices may be lower.” 

Biernbaum said that he believes the hoophouse concept is particularly popular with newer farmers — people pursuing second careers or young farmers unable to afford the larger acreage common  with  traditional farming.

A major part of the program is providing technical assistance to current and potential Michigan hoophouse farmers. MSU horticulture outreach specialists Adam Montri and Jeremy Moghtader and professional aide Laura Haselhuhn help to educate farmers on the topic.

Biernbaum categorizes the work into three phases:

  • First, MSU SOF hosts workshops where farmers learn the basics of selecting and building structures, and preparing the soil for planting. They also collaborate with the state of Michigan, the MSU Center for Regional Food Systems and the U.S. Department of Agriculture’s Natural Resources Conservation Service (USDA-NRCS) to provide loan or grant information for farmers. 
  • Second, focus is placed on understanding the particulars — what and how much to plant, and when and how to manage it organically.
  • Third, the team’s ultimate goal is helping Michigan hoophouse farmers be successful in production and profitability -- if that’s their end goal.

In 2011, AgBioResearch horticulturist Bridget Behe conducted a survey of SOF workshop attendees and hoophouse farmers.

“One outcome was that hoophouse users were often not able to make the income that is possible,” Biernbaum said. “Our focus now is to increase these farmers’ incomes and long-term productivity, to make their hoophouses successful, and to make hoophouses a way to provide jobs and year-round local food in Michigan.”

So what’s the future of research at the SOF?  Biernbaum is exploring composting methods and compost for organic nutrient management for hoophouses. He is also using a hoophouse for worm composting and cycling nutrients from campus food residue back to the farm. Biernbaum also wants to build a cold cellar. The cold storage method involves building a structure belowground, where the temperature is 40 to 50 degrees Fahrenheit. This reduces the farm’s energy needs for storing summer-grown vegetables for winter distribution.

Biernbaum believes the research has spurred advancements over the years.

“There is a new Michigan company called Nifty Hoops,” Biernbaum said. “The owner was part of a hoophouse workshop years ago, and he’s one example of how others have been able to build on the idea. Now he teaches people to build them, which is partially why our focus is able to shift to income. We’ve laid the foundation, and now we help it develop and grow.”

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