Wayward Springs LLC.
Increasing the Economic Viability of Year-Round High Tunnel Production in South Dakota’s Climate
Project Background
South Dakota specialty crop producers need energy efficient commercial/farm scale high tunnels that can enable growing specialty crops year-round in our harsh climate without reliance on expensive fossil fuels and high assembly costs. Local producers have seen natural gas prices increase 3X in the last 2 years severely limiting production.
Specialty crop production in South Dakota is limited to a narrow growing season (~109days) that limits the types of produce that can be cost effectively grown. High tunnels extend the growing season allowing common local produce such as tomatoes to be available longer but are still very limited without fossil fuels.
Advanced systems such as the Deep Winter Greenhouses (DWG) demonstrated by UMN have successfully taken season extension and operation cost savings further to facilitate year-round production of cool season vegetables such as lettuce, arugulas, broccoli & cabbages with minimal electricity & propane heat. However, the construction costs and materials are still quite high and not viable for many types of produce or year-round crops.
Deep Winter Greenhouse near Pillager, Minnesota
Prior work at Wayward Springs farm (SARE FNC19-1185) developed and demonstrated the effectiveness of a ground/soil-based heat storage system and provided valuable performance trade-offs. Weaknesses in the system were identified and will be built upon to improve heat capture, reduce assembly costs and provide better return on investment for growers. The greenhouse structure was complex, permanent and does not scale up cost-effectively to a commercial application. That prior experience combined with new information from other researchers will be leveraged to improve growing temperatures, reduce cost, and provide better guidelines to potential market and home growers interested in year-round food supplies in our local climate.
Wayward Springs Greenhouse, Brookings South Dakota
The most thoroughly researched and proven low-cost passive solar designs have been spearheaded by researchers from agricultural universities in China. These systems utilize thermally efficient structures with passive heat storage in a thermal mass wall. Performance in our colder, more northern USA climates are not proven and equivalent materials are not available in the USA. This project will evaluate the current state of the research, then apply and demonstrate the most recent guidelines for our climate.
Chinese Solar Greenhouse, Beijing Region, China
Image courtesy of Dr. Wenjing Guan
The objective will be to use or develop locally available materials. This state-of-the-art solar high tunnel concept will utilize & compare the cost and effectiveness of an air-soil heat storage system compared to the thermal mass wall concept. This system will focus on enabling producers’ maximum flexibility by enabling growing of perennial specialty crops that require in-ground planting. The system will utilize a non-permanent hoops and portable blocks that can be moved to a new growing bed if desired. The system could be modified for alternative growing methods like hydroponics or growing bags, but the focus of this project is for growing in the native ground/soil. The results will be used to provide guidelines to producers seeking the most cost-effective year-round systems for South Dakotans.
Traditional High Tunnel Greenhouse, Brookings South Dakota
Funding for "Increasing the Economic Viability of Year-Round High Tunnel Production in South Dakota’s Climate" was made possible by the U.S. Department of Agriculture's (USDA) Agricultural Marketing Service through grant AM22SCBPSD1128. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the USDA.