Evaluation of Flower Bud Removal Treatments on Growth of Young Blueberry Plants

The effects of flower bud removal treatments on growth of young rabbiteye ( Vaccinium ashei Reade) and southern highbush ( V. corymbosum hybrids) blueberry plants were evaluated. Treatments consisted of pruning, hand stripping, and hydrogen cyanamide applications. The growth index of rabbiteye plants after the first spring growth cycle was unaffected by any of the flower bud removal treatments. However, the effects of flower bud thinning were cultivar specific for southern highbush blueberry plants. ‘Misty’ plants showed increases in total plant dry weight and in root, leaf, and stem dry weights from hand thinning and hydrogen cyanamide sprays. Conversely, ‘Santa Fe’ showed no increased growth response from any of the flower bud removal treatments. Flower bud mortality increased as hydrogen cyanamide spray concentration increased and was greater when applications were delayed so that flower buds were more advanced. Hydrogen cyanamide may have potential as an alternative to labor-intense flower bud removal practices such as hand stripping or pruning on young blueberry plants during establishment.