Fertilizer rate and hedging intensity influences on the yield and fruit size of rabbiteye blueberry, cultivar Tifblue

Abstract

A field study was initiated to investigate the effects of two rates of N-P-K fertilizer, summer vs. winter hedging time, and three hedging intensities on yield and fruit size of mature rabbiteye blueberry (Vaccinium ashei Reade), cv. Tifblue. Yields were reduced by 45% the first year when no fertilizer was applied and 21% the fifth year of the experiment when half-rate fertilizer was used. No significant differences between full- and half-rate fertilizer effects were observed during the 2nd, 3rd, or 4th year of the study. However, the difference between the 5-year yield averages of full- and half-rates approached the 0.05 significance level indicating higher yield with the full rate of fertilizer. Winter hedging of 33 and 50% produced more fruit the last three years than the same hedging intensities in the summer. Fertilizer rate and hedging intensity interaction was significant for yield and fruit size for some years. Full-rate fertilizer produced more fruit on 100% hedging intensity than on 33% hedged plants. Half-rate fertilizer produced higher yields on 33% hedged plants compared to those hedged 100%. Fruit size was not significantly affected by the rate of fertilizer or the time of hedging. Hedging intensity did influence fruit size which varied from one year to another.