Pollination of about 7000 flowers of tetraploid highbush blueberry clones with pollen from a wild diploid species, V. elliottii (Chapm.) Small, gave 25 phenotypically obvious hybrids. Examination of 18 of these hybrids showed that they included triploids, tetraploids, pentaploids, and aneuploids. Some hybrids appeared to be mosaics, as evidenced by chromosome-number variability in premeiotic flower buds. Most hybrids were highly vigorous. The triploids were completely female sterile and the pentaploids ranged from partially to completely female sterile when open-pollinated. Three of the tetraploids examined were highly fertile and extremely vigorous. The occurrence of 3x-4x mosaicism suggests that the 3x hybrids may have arisen from chromosome loss in 4x plants rather than from 3x zygotes. Morphological similarities between certain of the 5x hybrids and the west Florida race of the native allohexaploid species V. ashei Reade suggest V. corymbosum L.–V. elliottii allohexaploidy as one possible mode of origin for V. ashei.