New greenhouse technology coming to Finland
Fresh locally, grown vegetables available to consumers during the winter months in Finland? It seems unlikely, but that's exactly what a new partnership between the University of Minnesota Extension Regional Sustainable Development Partnerships and Finland's Organic Consumers Association is hoping will happen.
Last month, RSDP announced a partnership with OCA to build a Deep Winter Greenhouse at the organization's Finland farm. A DWG is a passive solar, low-cost, low-carbon winter food production system. Farmers using DWG technology can grow winter-hardy crops like lettuce, cabbages, broccoli or Asian greens with little or no added heat. The structure is built with a south-facing sloped wall that captures heat from the sun. The heat is stored in a 4-foot deep underground rock bed and dissipates into the planting area during the night. The prototype developed at the University of Minnesota was based on earlier designs and increases insulation capacity and reduces the use of electricity or propane to heat the greenhouse.
Greg Schweser, associate director of local foods and sustainable agriculture for the RSDP, said temperatures in the greenhouse can reach more than 115 degrees, even during the coldest winter months. The greenhouse gets so hot that there is a ventilation system with a fan to cool the greenhouse and ensure the crops inside don't get burned.
"Existing common season extension techniques such as high tunnels and row covers extend the season, but are unable to provide capacity to produce product in the winter," Schweser said in a press release. "Passive solar Deep Winter Greenhouses optimize production in the winter months, giving farmers the ability to produce from October through March and bridge from the beginning to the end of the traditional production season."
OCA is a nonprofit formed in 1998 to pressure the federal government to keep strict organic standards and has grown to represent more than 2 million online and traditional activists in addition to producing some of its own fruit and vegetables. The group has grown to include seven employees and even helped establish a similar organization and small farm in Mexico City about five years ago.
The RSDP chose five sites in the different areas of Minnesota out of more than 40 applications and OCA's visibility was one of the main reasons it was chosen as a partner.
"There were a lot of good applicants but OCA really had the ability to help us really boost the visibility of this and we know that they can produce out of them as well," Schweser said.
Schweser said he estimates the greenhouse will cost about $30,000 to build, including all the materials and labor. The RSDP is going to provide $15,000 to OCA to help build the DWG and in return, the RSDP will be able to use the greenhouse for research and outreach purposes for three years.
"We're going to partner with people for three years to hold outreach and extension activities," Schweser said. "We're going to hold workshops and open houses and do research on building performance and production."
Schweser said as people begin using DWGs as opposed to high tunnel, or traditional greenhouses, the research and experimentation could lead to farmers growing other more traditional summer crops like peppers, tomatoes or cucumbers. For farmers whose production slows to nearly nothing in the harsh northern Minnesota winters, it could be have an enormous impact.
"The Deep Winter Greenhouse is just at the very beginning levels of this but we see that it works and there is enough evidence that this can work out there," Schweser said. "If this became as prevalent as high tunnels in Minnesota it could be a game changer for small scale and medium scale farming."