Northern Highbush Blueberries
Northern highbush blueberries are native to the eastern and northeastern United States. They grow from 5 to 9 feet tall. Highbush blueberries are naturally resistant to many diseases and pests. They are self-fertile, although produce better fruit if cross-pollinated with another Highbush variety in the vicinity. The fruit is plump and sweet, and great for making pies or eating raw.
These blueberries typically require a minimum of 600 chill hours in temperatures below 45 degrees Fahrenheit. They perform best in northern growing areas.
Southern Highbush Blueberries
These blueberries are hybrids of Vaccinum corymbosum and Florida species V. darrowii and were bred for growers in warm areas. The plants have a lower number of chill hours, ~200-300, required to produce fruit. The plants grow about 6 to 8 feet tall and produce small to large fruits, depending on the cultivar. Most are self-fertile, but will produce better with other Southern Highbush varieties planted nearby.
These plants may stay evergreen in warm climates and produce an earlier crop in the spring. The early crops are more susceptible to bird and deer foraging, and should be protected with netting or cages. Avoid planting these cultivars in cold areas, as a late frost can damage the flower buds.
Native to the southeastern United States, Rabbiteye blueberries are adapted to long hot summers. They grow from 6 to 10 feet tall on average and prefer highly acidic soil. They have few pests and are tolerant of poor soil. The berries are typically medium to large and flavorful, although older types produce fruit with more pronounced seeds.
These cultivars have a low threshold for chilling hours and do not grow well in cold climates, as they may be damaged by temperatures below 5°F. The berries will not ripen well in areas with mild summer temperatures. Rabbiteye blueberries are not self-fertile and require another Rabbiteye for cross-pollination and fruit production.
Lowbush blueberries (V. angustifolium) are native to parts of the Northern United States and the Maritime Provinces of Canada. They are typically wild shrubs found in open forests and sandy meadows. Lowbush blueberries as their name suggests stay low, under 1.5 feet, and rarely need pruning. They spread by underground runners and by self-seeding. Lowbush produces small, flavorful berries that are often used in commercial canning and production of jams and preserves.
Lowbush blueberries are not self-fertile and require either a lowbush or highbush blueberry for cross-pollination. They require highly acidic, well-drained soil with plenty of organic matter.