Location: Southern Horticultural ResearchTitle: Higher renovation pruning height improves early yields of ‘Woodard’ rabbiteye blueberry
|STAFNE, ERIC - MISSISSIPPI STATE UNIVERSITY|
Submitted to: HortTechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/26/2021
Publication Date: 2/23/2021
Citation: Stafne, E., Smith, B.J. 2021. Higher renovation pruning height improves early yields of ‘Woodard’ rabbiteye blueberry. HortTechnology. Volume 31:Issue 2/188-191. https://doi.org/10.21273/Horttech04782-20.
Interpretive Summary: Poorly performing and old rabbiteye blueberry bushes are widespread throughout much of the southeastern US. Owners are often hesitant to perform drastic renovation pruning because it eliminates most fruit production in the following year or more. The purpose of this study was to determine how pruning height affects blueberry plant growth, fruit quality, and total yield in the second and third growing seasons after treatment. At the start of this study, the 30-year-old bushes were in very poor health, and their fruit was less than desirable in both yield and quality. By the third year after pruning, bushes pruned at a 50-cm height produced more canes and more fruit than bushes cut at ground level. Growers and extension personnel will benefit from the recommendation of pruning bushes 50-cm above ground level when doing renovation pruning of rabbiteye blueberry which will lead to earlier and higher yields than cutting bushes back to the ground level.
Technical Abstract: Rabbiteye blueberry bushes (Vaccinium virgatum Aiton) are relatively easy to grow and are commonplace across Mississippi; however, if not properly cared for the bushes will decline over time. Eighteen old, unproductive ‘Woodard’ rabbiteye blueberry bushes were pruned at two different heights (ground level and 50 cm above ground level after harvest in July 2017) and phosphorous acid was applied as a drench and a foliar spray in the first year, but was discontinued because they had no effect on the bushes. Fruit yields were collected and weighed, bushes were measured for growth parameters, and canes weighed. Bushes pruned at 50 cm had much higher yields in both 2019 (3.47 kg vs. 0.63 kg) and 2020 (3.91 kg vs. 1.23 kg). Pruning at 50 cm vs. ground level provided a substantial yield benefit. The 50 cm treatment bushes produced more canes by the end of the study, thus accounting for more fruiting area, as seen in the harvest index. In short, pruning old, non-productive bushes at 50 cm can provide growers with greater early returns than pruning at ground level for ‘Woodard’ rabbiteye blueberry.