2018 ASHS Annual Conference

Strawberry growers in Florida generally apply 168–224 kg of nitrogen (N) per hectare during the growing season, starting with 1.96–2.24 kg/ha/d during establishment followed by lower rates at 0.56–1.12 kg/ha/d. The initial high-dose fertilization is beneficial for improving the establishment of strawberry transplants, but this practice must be tailored for each cultivar based on its growth characteristics and nutrient requirements. The objective of this study was to determine the optimal early-season fertilization program for ‘Florida Beauty’ strawberry, which is a newly developed early-yielding cultivar. Treatments were different durations of the high N fertilization at 2.24 kg/ha/d during the early season: 0, 3, 6, and 9 weeks. After these treatment durations, all treatments were subjected to the lower rate at 1.12 kg/ha/d, providing 149 to 243 kg of N in the growing season. Transplants were planted in the field on Sep. 28, 2017, and harvests were performed 30 times between Nov. 2, 2017 and Feb. 26, 2018. Extending the high N fertilization duration from 0 to 9 weeks accelerated initial canopy development and increased leaf N concentration by up to 8% until late Jan. It also increased the early yield (Nov.–Jan.) by 33% and the total season yield by 28%, while reducing the thrip-damaged fruit by up to 53% in the entire season. These results suggest that extending the durations of the high N fertilization for up to 9 weeks is effective in developing healthy and productive canopy, thereby improving fruit yield and earliness of ‘Florida Beauty’.