Blueberry grapes are small to medium in size and round to oval in shape. The smooth skin ranges in color from deep purple, navy blue, to almost black. The flesh is translucent green and firm. Blueberry grapes grow in tight and dense clusters, and each berry has a thicker skin than most grapes found in the commercial markets. Blueberry grapes boast a bright, slightly tart, mild blueberry flavor and are very juicy.