Do cranberries grow on a tree or a bush?

Neither. The American Cranberry (Vaccinium macrocarpon) is a low-growing, vining, woody perennial plant with small, alternate, oval leaves. The plant produces horizontal stems or runners up to 6 feet (2 m) long. Short vertical branches 2 to 8 inches (5 to 20 cm) in height, called uprights, grow from buds on the runners and produce both vegetative and fruit buds. Each fruit bud may contain as many as seven flowers.