Advancing Primocane-fruiting Raspberry Production in the Intermountain West Using Spring Protection

Abstract

Winter injury to raspberry floricanes commonly limits productivity in cold climates. Primocane-fruiting raspberries avoid winter injury by fruiting on first year canes, but fruit production in the high-elevation valleys of the Intermountain West is later than needed for local markets, and may be limited by early fall freezes. High tunnels were used for early spring heat to advance primocane growth and the fruiting season of two primocane-fruiting red raspberry cultivars. Tunnels were covered with plastic in March and April. Then, they were covered with shade cloth during fruit ripening. Tunnel-covered plots were compared with field plantings for primocane growth rate, fruiting season, yield, and fruit quality over two seasons. High tunnels increased cane growth rate, with the harvest season advanced by 18 to 26 days depending on season and cultivar, but they did not consistently affect the total season yield or fruit size. Low-cost two-season tunnels used in conjunction with early-season primocane-fruiting raspberries may provide a viable method for small acreage producers in harsh climates to reliably supply high-value seasonal raspberry markets.