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Boreal Community Media

New deep winter greenhouse allows Grand Portage community to grow food year round

Apr 25, 2023 08:33AM ● By Content Editor
All photos by Laura Durenberger-Grunow 

By Laura Duenberger-Grunow - Boreal Community Media - April 24, 2023


Imagine being able to grow your own food in NE Minnesota year-round. It’s a dream that the majority of local gardeners can’t believe. 

But that exact concept has become a reality for the Grand Portage Community with the installation of a deep winter greenhouse. 

Deep Winter Greenhouses are a relatively new project that was developed by the University of Minnesota Extension and the U of M College of Design.  

What is a deep winter greenhouse?

The U of M defines a deep winter greenhouse (DWG) as “ a greenhouse that is designed to limit the amount of fossil fuel it takes to grow crops during cold winters. DWGs are passive-solar greenhouses that rely on energy from the sun to heat the building instead of more traditional heating sources.

 A south-facing glazing wall is an important component in DWG design


An important component of a successful DWG is picking a location where an angled glazing wall can face south; in order to capture as much solar energy as possible. As the sun heats the air inside the greenhouse, a fan blows the warm air underground, which is then stored in a thermal mass made of rock or soil. 

In the case of the DWG in Grand Portage, rocks underground are used for heat storage.  

At night, the rocks or soil release the heat back into the structure. 

To learn more about the greenhouse and how it came to fruition, Boreal Community Media spoke with Emily Derke, Agriculture Coordinator, Agatha Armstrong, Grand Portage Tribal Council Member, and Andrew Duhaime, former Agricultural Coordinator and regular greenhouse volunteer. 

 The greenhouse provides welcome warmth during the cold winter months


It was a cool April day outside, but inside the Grand Portage Deep Winter Greenhouse, it was a warm 80+ degrees Fahrenheit. A community open house was being held for anyone who wanted to come to visit the new structure - which many took advantage of. 

After walking inside the greenhouse and feeling the warmth, community members remarked on the numerous raised beds filled with different types of lettuce, tomatoes, and peppers. (Yes, in April.) There were lots of smiles and expressions of joy.

Developing the project

Discussion around building a greenhouse started in 2018 when a committee of Grand Portage community and Council members applied for a grant to help the community further their goal of food sovereignty. 

“We’re at the end of the road when it comes to food distribution. Often, fresh food will arrive within 1-2 days of expiration,” said Armstrong, who was on the project committee. 

“We were looking for a way to provide the community with fresh food that we could grow ourselves.” 

The grant was awarded, a site was selected, and plans from the U of M were obtained. 

Armstrong added that “We picked the site because of the proximity to the waste station, which has a composting machine. Additionally, the site already had availability to water.”

Then the pandemic hit, and progress halted. 

Andrew Duhaime was the one who stepped in and got the project rolling again after the Agricultural Coordinator at the time got a new job. 

“I took over for someone who had a lot of plans and projects, and the greenhouse was one of them,” he said. 

Duhaime shared that he started calling local contractors looking for anyone who could help get the construction going. 

“Due to the pandemic, I wasn’t getting a lot of callbacks. But, through a stroke of luck, I got in contact with someone who could help,” he added. 

The first part of the project involved clearing a space on the designated land, which was covered in red pines. Duhaime got in touch with a local forester, who jumped in to help. 

Once the land was cleared, the project could begin. 

 Photos of construction were available for all to see at the Community Open House


Fast forward to the summer of 2021, and it was around that time that Duhaime left his position as Agricultural Coordinator. But, just because he left the position, didn’t mean he didn’t want to be involved. 

“I have a huge passion for gardening and growing food, so I would continue to check in with the project to see how progress was going, even after I left.” 

(Duhaime is so passionate about gardening that he runs his own YouTube channel at Grand Portage Gardener.)

By the time summer of 2022 rolled around, Emily Derke was starting in her position as the current Agricultural Coordinator. 

Derke asked Duhaime for assistance, and together they looked over plans and determined the next steps. 

In November 2022, Duhmaine built all of the raised beds, ordered the soil, and hung the greenhouse fans. 

Finally, in December 2022, the greenhouse was ready for planting. 

A period of discovery

Being that it was December, one of the big questions was figuring out what to plant that can tolerate shorter daylight hours. 

“With the DWG and figuring out what to grow, it’s less about temperature and more about daylight length. Even though it’s warm in here, the days are too short to grow things like tomatoes and peppers year round”, Derke said. 

Figuring out what can grow (and when) is something Derke and Duhaime both say is something that’ll take time to determine, and remains one of the bigger challenges in the project. 

So far, lettuce seems to be a safe cold, short-day length weather crop, and one that has not only been successfully grown on-site but also shared within the community. 

 Lettuce has been successful during the cold weather months when daylight is limited


Through a partnership with Oshki Ogimaag Charter School, students have been repeating visitors to the greenhouse. 

With Derke and Duhaime’s assistance, the students have been able to plant, tend, and harvest lettuce, then deliver the greens to the Elderly Nutrition Program. 

The greenhouse has also already been incorporated in partnership with other lessons the students are learning.

Earlier in the winter, students set up snowshoe hare traps with community member Erik Redix around the land the greenhouse sits on. They would repeatedly come out and check the traps, and at the same time, stop in to check on the leafy greens they planted. 

Eventually, they were able to enjoy a meal that included snowshoe hare and a salad - both items that they had a hand in obtaining. 

Both Derke and Duhaime mentioned that having the Oshki students out at the greenhouse has been exciting and rewarding. 

“I love having the students at the greenhouse, and it's definitely something we want to continue moving forward. One of the things we’re still trying to figure out is the balance between using the space as an area for students, while also using the space to grow food to give back to the community,” Derke said. 

During the warmer months, food that is grown will be donated to the CACHE Farm Market, in addition to the Elderly Nutrition Program, and Summer Food Program. 

As for what else the future of the project holds, Duhaime has some ideas. 

“I’d love to see the fields around the greenhouse become more community gardens (with a focus on creating accessible raised beds that are around hip height), and maybe an orchard.” 

As for Derke, her focus for the next year is to allow the project to become more established by continuing to incorporate students, while also learning what can be grown (and when), so the greenhouse can be utilized to maximize food production as much as possible. 

“Honestly, the best part about this project is being able to give food back to the community”, Duhaime said. 

 A small storage area connects to the main greenhouse right inside the door


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