Intercropping With Oyster Mushrooms

Farm Name: Granite Springs Farm
Operator Name: Meredith Leight
Production: vegetables, livestock, horticulture
Markets: Farmer’s markets, CSA, restaurants
Location: Pittsboro, Chatham County, NC

Granite Springs Farm is a diversified small farm in Chatham County. The farm supplies produce to several restaurants in the Triangle area, serves three farmer’s markets, and has a growing CSA.

Meredith Leight started the farm several years ago as a “radical expression of hope” as her husband was dying of cancer. Since his passing, she and her young daughter have kept the farm going strong, growing their operation and their consumer base every year. Meredith’s background is in banking and teaching. She received a degree from UNC-Chapel Hill in education and had made a career in those two fields. She still uses these backgrounds in the farming world by using her teaching skills to educate the public on sustainably raised foods and her banking skills to manage the farm business.

In 2012, Meredith applied for a grant to further diversify Granite Springs Farm’s operation. The farm has a hoophouse that originally was used to start tobacco plugs before they would be set out in the field. The hoophouse has since been converted into a place to grow vegetables to extend the season and keep plants sensitive to moisture at the proper watering levels. Leight wanted to expand her operation and start growing oyster mushrooms. She wanted to see if the hoophouse would be an ideal space to grow mushrooms and found that she could hang bags of inoculated substrate from the roof of the structure, having mushrooms fruit while suspended in the air above the crops planted in the beds beneath. This system could take advantage of the vertical space that hoophouses have and allow optimal production to occur within the space. Meredith hopes to grow crops that would be complimentary to the mushrooms like ginger, tomatoes, and other warm season vegetable crops.

Growing oyster mushrooms is a relatively simple process although they behave inherently different from other edible crops. They require a humid environment in order to fruit and they are grown on a carbon-rich substrate, typically straw or sawdust, with a few added nutrients to encourage healthy mushrooms. Mushrooms can also take advantage of agricultural and forestry by-products by re-using them as a fruiting substrate. The substrate after it has been used up by the fungi can then be composted for use in crop production. Growing mushrooms can increase farm sustainability by closing the cycle through using agricultural waste and eventually becoming a soil additive for crop production. Mushrooms fruit best in indirect light; some farmers cultivate them in the woods or under a thick shade cloth, but Meredith wanted to determine whether a hoophouse could sufficiently filter light for mushroom growth as well. Meredith also wanted to grow them inside the hoophouse to avoid many uncontrollable factors that come with growing such a sensitive crop outdoors (i.e. several pests, weather changes, and other types of damage. Inside the hoophouse she can keep the fungi in a consistent environment, ensuring long, high-yield fruiting cycles.

Granite Springs Farm’s oyster mushroom cultivation project will bring the farm closer to being fully sustainable by producing a highly profitable food and medicinal product, optimizing a redesigned farm structure, and rerouting waste streams to produce a new product and ensure long-term fertility in the beds and fields.

RAFI’s grant program is supported by a generous grant from the NC Tobacco Trust Fund Commission.