Blueberry (Vaccinium corymbosum interspecific hybrids) production in many regions of the world requires significant investments, including the use of soil amendments like pine bark. Prior research has identified V. arboreum as a potential rootstock which may reduce the need for costly soil inputs for growing southern highbush blueberries (SHB). Furthermore, use of V. arboreum as a blueberry rootstock may improve drought tolerance, increase plant longevity, confer tolerance to bacterial leaf scorch (Xylella fastidiosa), and make mechanical harvesting more feasible. However, V. arboreum propagation and grafting can be challenging. Thus, there is a critical need to develop nursery practices for the production of grafted blueberry liners. Preliminary observations suggest that interspecific hybrids of SHB × V. arboreum may have desirable rootstock characteristics like greater rooting success and wider scion compatibility than V. arboreum. This study aimed to identify optimal grafting practices by evaluating the effects of different grafting timings on subsequent plant development of SHB grafted onto SHB × V. arboreum hybrids and V. arboreum rootstocks. ‘Sentinel’ and ‘Albus’ SHB scion cultivars were grafted onto V. arboreum and hybrid rootstocks at four times in the year: February, March, September, and November. Scion takes and growth were evaluated. Grafting success and subsequent plant development were assessed using a bud development scale. Results showed that grafting in the spring improved scion development compared to fall grafting. Additionally, hybrid rootstocks exhibited greater compatibility with SHB scions than V. arboreum. The findings from this project will contribute to the optimization of nursery practices for producing grafted SHB nursery plants efficiently which is necessary for adoption of rootstock use in commercial blueberry production.
