PROPAGATION, NURSERY CONTAINER PRODUCTION, AND RHIZOME GROWTH STUDIES OF Vaccinium angustifolium Ait. AND Vaccinium vitis-idaea L. subsp. minus (Lodd.) Hultén

Lowbush blueberry (Vaccinium angustifolium Ait.), and lingonberry (Vaccinium vitis-idaea L.) are low shrubs that are native to Maine and spread by growth of underground stems called rhizomes. They are valuable species for use as commercial small fruit crops as well as ornamental landscape plants. Stem cuttings can provide a convenient and inexpensive propagation method for many plants and can be a more efficient use of stock plants than division of rhizomes. Stem cuttings are generally not lost due to contamination and do not require the specialized techniques involved in tissue culture. A stem cutting propagation study of the native Maine lingonberry [Vaccinium vitis-idaea L. subsp. minus (Lodd.) Hultén] determined that the highest rooting percentage and largest rootballs would be obtained from lingonberry stem cuttings of current season’s growth collected in the fall. Successfully propagated selections of superior clones (genotypes) of lowbush blueberry and lingonberry should be grown in a production system providing an ideal container medium with optimum fertility and irrigation. A container nursery production study of lowbush blueberry concluded that relatively wide and shallow nursery containers, like a nursery mum pan, would be better for nursery production of lowbush blueberry than a traditional nursery container. A container medium with sphagnum peat moss and coarse sharp sand would also promote more shoot growth than a bark based nursery mix. Increasing rhizome growth of lowbush blueberry will benefit commercial growers by filling in bare areas in fields or increasing the rate of establishment of new plantings and also enhance the use of lowbush blueberry as an ornamental landscape groundcover. Three field studies assessed the effects of growth regulators on rhizome growth of lowbush blueberry. The results indicated that prohexadione-calcium (calcium 3-oxido-5-oxo-4-propionylcyclohex-3-enecarboxylate), a gibberellin synthesis inhibitor, increased rhizome growth of lowbush blueberry, but concentration and timing of application are important. Sucrose drenches were also evaluated for improving rhizome growth of lowbush blueberry. Although sucrose drenches were not effective in this study, it appeared that applications may have been made too late in the growing season to promote rhizome growth. Further evaluation of sucrose drenches for increasing rhizome production of lowbush blueberry, as well as lingonberry, is warranted.