MANAGING THE GROWTH AND FRUITING OF RABBITEYE (VACCINIUM ASHEI READE) BLUEBERRIES WITH PRUNING AND GROWTH REGULATORS
Winter pruning to control the height of excessively vigorous rabbiteye plants often results in declining yields. When bush height exceeds 1.8 m, hand harvest is difficult and inefficient. Mechanical harvesting problems occur when bush heights exceed 2.4 m. Mature cv Delite bushes yielded an average of 4.6 kg for the 1984 through 1987 harvest seasons when summer pruning in late July was combined with winter pruning. With winter pruning alone, the yield was 3.0 kg/bush. Weight per berry was 0.12 greater with the combination of summer and winter pruning than with winter pruning alone. Summer pruning consisted of cutting vigorous shoots more than 30 cm long that were initiated above a 90 cm height in the bush. Without summer pruning, the vigorous canes grew to a length of 90 to 120 cm, developed very few flower buds and provided undesirable shade to shoots lower on the bush that were forming flower buds. Time required for the combination of summer plus winter pruning was 11.3 minutes compared with 10.4 minutes for winter pruning. Soil applications of the growth regulating chemical, [4-chlorophenyl) methyl)]--(1,1-dimethylethyl)-H-1,2,4-triazole-1-ethanol (paclobutrazol) reduced the vigor of mature 'Tifblue' plants, however, at the lowest effective rate of 2 g ai/plant, yields were also reduced.
Mainland, C.M. (1989). MANAGING THE GROWTH AND FRUITING OF RABBITEYE (VACCINIUM ASHEI READE) BLUEBERRIES WITH PRUNING AND GROWTH REGULATORS. Acta Hortic. 241, 195-200