Late-season Strawberry Production Using Day-neutral Cultivars in High-elevation High Tunnels

Abstract

Small-scale fruit and vegetable growers increasingly use high tunnels to expand production windows and exploit demand for local produce. Day-neutral cultivars, high tunnels, low tunnels, and targeted heating were investigated in North Logan, UT (lat. 41.766° N, 1405 m elevation, 119 freeze-free days) to extend the availability of local strawberries. Day-neutral cultivars Albion, Evie 2, Seascape, and Tribute were spring-planted in an annual hill system both inside and outside of high tunnels. Within the high tunnels, low tunnels and targeted root zone heating were tested in replicated plots. During the summer months, plastic was removed from the high tunnels and replaced with shadecloth. Treatments were evaluated for yields, fruit size, and production season. Fruit production in the tunnels began in late May and continued sporadically until December. Combinations of high and low tunnels provided more hours of optimal growing conditions than high tunnels alone, but managing the combination to maintain optimum temperatures proved difficult with temperatures often exceeding the optimum for strawberry. Targeted root zone heating efficiently increased root and canopy temperatures, preventing flower bud damage during extreme cold events, but did not significantly improve total season yields. Of the cultivars tested, ‘Evie 2’ and ‘Seascape’ had the most consistent yields and acceptable fruit size. Economic analysis indicated that growing spring-planted day-neutral strawberries in high tunnels was marginally profitable, whereas field production at this location would be a money-losing enterprise.