Earth sheltered greenhouse A year-round grow space for northern gardeners By Dan Rubin
Winter weather here in the north requires protected grow space.
T
he basic principle is simple: if you live north of the 40th parallel, building a greenhouse with clear walls on all sides makes absolutely no sense. Since sunlight will never enter through the north side of the building, that side should be insulated rather than transparent, to retain heat. This simple concept was brought home to me by Elke Dettmer, my nextdoor neighbour, here in the outport town of Pouch Cove, Newfoundland. Elke needed a greenhouse. She mentioned she was thinking of building one into the side of the hill, facing south toward the open Atlantic. As soon as the earth sheltered concept crystallized in my mind, I began to wonder how it would work. What would it take to build one? How much would it cost to heat? I just couldn’t shake the idea of 34 • 2021
the greenhouse “with its arse in the earth.” Memorial University gets involved When I met Marc Kielley, a project director at Memorial University, at a greenhouse conference in St. John’s, he suggested I should contact Andrew Fisher, vice-dean of engineering. Andy was able to offer the services of two co-op students to turn the basic idea into a design. So my quest continued. Within a year, a third student had pitched in, and then we had the design down on paper: the Earth Sheltered Greenhouse would be a year-round grow space for vegetables, flowers and fruit. Once we evaluated cost of construction materials and heating, we knew we had something special. For a 12-by-20-foot building, cost of materials was less than $10,000 and baseIssue 4
board electrical heat would add less than $400 per year. So this was more than just a greenhouse; it was a game changer! The Earth Sheltered Greenhouse would allow people in a rural town to grow healthy food for their community at low cost. When I brought this design to a meeting with the staff of the Memorial University Botanical Garden a year later, things began to move fast. I presented our plan hoping for some mild interest. But Kim Shipp, director of the Garden, was more than interested: she immediately committed to help build it. She also shared some sage advice: in order to get in line for funding from the university and make sure our design was solid, we would first apply for a start-up grant to thoroughly evaluate the design, by bringing together the best local stakeholders we could identify. localgardener.net
