GREG Winter Greenhouse Production of Specialty Greens: Profiting from Solar Heating

Project Leader: Lynn Gillespie, Paonia, CO

Technical Advisor: Ron Godin, Research Scientist, CSU Rogers Mesa Experiment Station, Hotchkiss, CO

Project Years: 2004, 2005, 2006

Lynn Gillespie

Project Summary

The demand for organic specialty greens in the winter in Colorado is very high. Growers are having a hard time keeping up with this demand, and so California sources are tapped. This diminishes the amount of crops grown in the state and the income from them. The cost of heating a greenhouse using propane to grow specialty green in the winter makes the profit margins small to non-existent. If Colorado growers could utilize the 300+ days of sunshine and greenhouses’ solar-heating potential, it would increase profits as well as being environmentally friendly by not using fossil fuels.

The specialty greens will be grown in a 30 by 60 foot greenhouse. Inside the greenhouse are several cinderblock-framed production beds. The base of the beds are filled with gravel to serve as heat storage. Above the ground are soil beds in which the plants are grown. The plants are covered in the evening to conserve warmth. A fan draws heat from the greenhouse peak and pumps it through perforated pipes buried in the gravel beds.

Crop yields will be tabulated along with corresponding income and total costs to see if a profit can be made by growing specialty greens in a solar-heated greenhouse compared to a propane-heated greenhouse.

Click here for a link to the full text of the 2004 Annual Report (Word document).