Locally produced organic apples are in demand, but most organic apples are produced in desert areas of Washington, where the dry climate reduces infection from fungal diseases such as apple scab. In the north central U.S., wetter weather favors disease, and most organic apple growers grow disease-resistant varieties and/or spray organic fungicides such as sulfur. Disease-resistant varieties can be difficult to market if they are not the most flavorful varieties or if they are not familiar to consumers. Organic fungicide sprays are expensive, require frequent re-application, and can have negative effects on apple trees, beneficial insects, and the environment. I propose to evaluate the profitability of organic apples grown in unheated polyethylene-covered high tunnels. Trees in tunnels are protected from rain and should therefore suffer less disease. Tunnels can also ameliorate severe weather, provide better growing conditions, and thus improve yields. Although high tunnels are expensive to build, many growers already have tunnels or can construct them at low cost with USDA-NRCS EQIP grants. I will compare seven apple varieties in our project: high tunnels may be best suited to disease-susceptible varieties which are difficult to grow outdoors but which command a high market price.
Project objectives from proposal:
- Measure costs, yields, and profitability of organic apples raised in high tunnels
- Compare yields and profitability of seven apple varieties in high tunnels
- Measure incidence of common apple diseases and insect pests in high tunnels
- Share results with other growers through our website, field days, emails to grower list-serves, articles in grower publications, and a conference poster session.