Growth, yield and fruit quality of organic day-neutral strawberry in field and low tunnel settings in the southeastern United States

Low tunnels (LT) have emerged in recent years to extend the harvest season of day-neutral strawberries. The objective of this research was to examine if LT and planting dates would affect the growth, yield and fruit quality of day-neutral strawberries in the southeastern US. The experimental design was a completely randomized design, conducted as split-split plot design with three replications. Cultivars 'Albion' and 'San Andreas' were planted on September 1, 2016 or September 9, 2017 (D1), and on September 29, 2016 or October 10, 2017 (D2) in Greensboro, North Carolina, which is in USDA plant hardiness zone 7b. LT did not affect plant canopy size and biomass in year 1, but increased plant canopy size and biomass in year 2. D1 plants had greater monthly biomass and canopy size than D2 plants. Planting dates affected the time of first bloom and harvest. Plants of D1 bloomed much earlier than plants of D2. LT significantly increased the marketable yield and total yield in year 2, but not in year 1. Plants of LT had higher rate of marketable fruit than plants of open field. D1 plants had higher total yield than D2 plants. LT did not change the single fruit weight and generally did not affect the berry °Brix. The yields of 'Albion' and 'San Andreas' were not significantly different in both years. This 2-year study suggests LT to be a useful tool for organic day-neutral strawberry production in the region.