Wrong type or you got caught by a late frost. I grow rabbiteyes and southern high bush with few problems. Actually none for the rabbit eyes. The northern types may be "iffy" even in Rome. Soil needs to be acidic but that would show up in the appearance of the plants before fruiting.
I don't know if this applies to your bushes or not, but I read this:
The wild blueberry bush has a 2 year cycle, which means that every other year a blueberry bush will produce berries. During the year that no berries are produced, the farmers try to help the vegetative growth to increase. This helps the general health of the blueberry bush as a whole plant. During a blueberry-producing year, the plant is prepared for an August harvest, when the blueberries will be ready for picking.