Labor Costs and Yield Recovery after Renovation and Cane Thinning in ‘Mini Blues’ Highbush Blueberry

‘Mini Blues’ highbush blueberry ( Vaccinium sp.) was released in 2016 as a high-quality, machine-harvestable cultivar for processed markets. A planting was established in Oct 2015 in western Oregon and an initial study, published in 2022, included the following pruning treatments, which began in Winter 2017–18: 1) conventional highbush pruning (HB); 2) removing one or two of the oldest canes per bush (Speed); 3) leaving plants to grow from 2017–21 (Unpruned); and 4) hedging after fruit harvest in 2018 (Hedge) and then unpruned afterward. Hedge plants were considered identical to Unpruned at the end of the initial study. In Winter 2021–22, this study began when Unpruned and Hedge treatment plants were renovated by cutting all canes back to a height of ∼30 cm and thinning to the strongest 8 to 10 canes per plant. In Winter 2022–23, half of the renovated plants were thinned (“cane thinning”), leaving 10 to 12 strong canes, and the other half were left unthinned. Pruning time, yield, berry weight, and total soluble solids (TSS) were measured from 2022 to 2024 to determine how quickly plants recovered from renovation and what the economic considerations are for this practice given the loss of yield in 2022 after renovation. Cane thinning in Winter 2022–23 reduced yield compared with all other treatments in 2023, but all treatments had similar yield by the third season after renovation (2024). Berry weight and TSS were similar among treatments, except Speed had smaller berries in 2023. Cane thinning required 331 h/ha compared with 44 h/ha for Unthinned (removing low growth) and 376 h/ha for HB in 2022–23. The highest post-renovation economic returns, as well as cumulative returns (2018–24) came from Speed pruning, followed by unpruned with renovation and no cane thinning. Cane thinning reduced yield for 1 year, cost more for labor, and showed no significant benefit in the 2 years since it was performed. ‘Mini Blues’ continues to perform well with reduced labor practices and does not need to be pruned using conventional techniques.