Abstract: Cranberry (Vaccinium macrocarpon Ait.) is one of the few native fruit crops from North America, and Wisconsin is one of the main producers nationwide. Fruit production in cranberry fields rely on the ability of the uprights (vertical stems) to set buds with floral meristems for the following growing season. However, little is still known about bud formation and floral meristem development in cranberry cultivars. This study evaluates the presence and differentiation of floral initials within apical buds. Longitudinal and cross sections from both vegetative and fruiting uprights of two cultivars were analyzed. Periodical collections and histological analysis revealed differences in bud formation and floral meristems development between cultivars and upright types, across the growing season (June to August) and through dormancy (September to April). Note: The presentation is not available to download.