2017 ASHS Annual Conference

Out-of-season organic strawberry production, has proven to be profitable, by filling a gap in fresh markets throughout North Carolina. However, a cold damage of 61.5% to open blossoms was observed in our previous study. The objective of this project was to evaluate the efficacy of using low tunnels inside an existing high tunnel on harvest times, yield and cold weather protection. Four June-bearing varieties Benecia, Camino Real, Radiance, and Winterstar were planted in September 2016 on North Carolina A&T State University Research Farm in Greensboro, North Carolina. The high tunnel was 30’ (W) x 96’ (L), managed organically and has a single-layer 6-mil polyplastic cover. Low tunnels consisted of a galvanized metal wire covered with 1-mil perforated plastic. The experimental design was a completely randomized design, conducted as a split-plot with three replications. The main plots were beds mulched with black plastic with or without low tunnel covers; the split plots were cultivars. Each split-plot had a total of 42 plants, 18 of them were used for yield collection and the rest for biomass collection. Preliminary results from data prior to March 1, 2017 showed that cold damage to open blossom, marketable yield, and total yield were not affected by low tunnels. The freezing damage to open blooms in January, marketable yield and total yield with or without low tunnels were 17.6 and 12.8%, 424.2 and 425.0 g/plot (18 plants), and 493.7 and 449.0 g/plot, respectively. There were significant differences between varieties on yield. ‘Radiance’ (778 g/plot) and ‘Winterstar’ (608 g/plot) produced a significantly higher yield than ‘Camino Real’ (99 g/plot) and ‘Benecia” (214 g/plot). The cold damage to open blooms in January was not significantly different between cultivars, the number ranged from 12.3% for ‘Radiance’ to 20.5% for ‘Winterstar’. Future plans for this project include the completion of harvest and fruit quality analysis for the remainder of the current season. The entire project will be repeated in 2017/18.