2018 ASHS Annual Conference

Carol Miles*, Vegetable Extension Specialist, Washington State University

Heather Stoven, Extension Horticulturist, Oregon State University

Rob Brown, Flattop Farm, Anchorage, Alaska

*presenting author

The use of high tunnels has been somewhat slow to become established in Washington and Idaho, whereas in Oregon high tunnels have been used for several decades in the nursery industry. Direct market farms in the urban periphery in the region use high tunnels predominantly for tomato in the summer and salad greens in the winter. Our research showed that late blight (caused by Phytophthora infestans), the disease most limiting tomato production in the region, could be controlled by growing tomato in high tunnels with appropriate management conditions (e.g., good ventilation, not overly high relative humidity). Temperature throughout the winter in western Washington and Oregon tends to be relatively mild, and cold-tolerant crops can be grown in high tunnels with minimal additional protection. In contrast, most of Alaska has very cold winter temperatures, high winds and high snowfall; about $4 mil. has been awarded by NRCS for high tunnels in Alaska. High tunnels in Alaska must be constructed with additional structural support to withstand winter weather.