Blueberry
Blueberries are a widely distributed and widespread group of perennial flowering plants with blue or purple berries. They are classified in the section Cyanococcus within the genus Vaccinium. Commercial blueberries—both wild and cultivated —are all native to North America. The highbush varieties were introduced into Europe during the 1930s.
Blueberries are usually prostrate shrubs that can vary in size from to in height. In the commercial production of blueberries, the species with small, pea-size berries growing on low-level bushes is known as "lowbush blueberries", while the species with larger berries growing on taller, cultivated bushes is known as "highbush blueberries". In 2024, Canada was the leading producer of lowbush blueberries, while the United States produced 29% of the world's supply of highbush blueberries.
Description
Many species of blueberries grow wild in North America, including Vaccinium myrtilloides, V. angustifolium and V. corymbosum, which grow on forest floors or near swamps.Wild blueberries reproduce by cross pollination, with each seed producing a plant with a different genetic composition, causing within the same species differences in growth, productivity, color, leaf characteristics, disease resistance, flavor, and other fruit characteristics. The mother plant develops underground stems called rhizomes, allowing the plant to form a network of rhizomes creating a large patch which is genetically distinct. Floral and leaf buds develop intermittently along the stems of the plant, with each floral bud giving rise to 5–6 flowers and the eventual fruit. Wild blueberries prefer an acidic soil between 4.2 and 5.2 pH and only moderate amounts of moisture. They have a hardy cold tolerance in their range in Canada and the northern United States. Fruit productivity of lowbush blueberries varies by the degree of pollination, genetics of the clone, soil fertility, water availability, insect infestation, plant diseases, and local growing conditions. Wild blueberries have an average mature weight of.
Lowbush blueberries, sometimes called "wild blueberries", are generally not planted by farmers, but rather are managed on berry fields called "barrens". Cultivated highbush blueberries prefer sandy or loam soils, having shallow root systems that benefit from mulch and fertilizer. The leaves of highbush blueberries can be either deciduous or evergreen, ovate to lanceolate, and long and broad. The flowers are bell-shaped, white, pale pink or red, sometimes tinged greenish.
The fruit is a berry in diameter with a flared crown at the end; they are pale greenish at first, then reddish-purple, and finally uniformly blue when ripe. They are covered in a protective coating of powdery epicuticular wax, colloquially known as the "bloom". They generally have a sweet taste when mature, with variable acidity. Blueberry bushes typically bear fruit in the middle of the growing season: fruiting times are affected by local conditions, such as climate, altitude, and latitude, so the time of harvest in the northern hemisphere can vary from May to August.
Identification
Commercially offered blueberries are usually from species that naturally occur only in eastern and north-central North America. Other sections in the genus are native to other parts of the world, including the Pacific Northwest and the southern United States, South America, Europe and Asia. Other wild shrubs in many of these regions produce similar-looking edible berries, such as huckleberries and whortleberries and bilberries. These species are sometimes called "blueberries" and are sold as blueberry jam or other products.The names of blueberries in languages other than English often translate as "blueberry", e.g. Scots blaeberry and Norwegian blåbær. blaeberry, blåbær and French myrtilles usually refer to the European native V. myrtillus, while bleuets refers to the North American blueberry.
Species
Note: habitat and range summaries are from the Flora of New Brunswick, published in 1986 by Harold R. Hinds, and Plants of the Pacific Northwest coast, published in 1994 by Pojar and MacKinnon.- Vaccinium angustifolium : acidic barrens, bogs and clearings, Manitoba to Labrador, south to Nova Scotia; and in the United States, from Maine westward to Iowa and southward to Virginia
- Vaccinium boreale : peaty barrens, Quebec and Labrador, south to New York and Massachusetts
- Vaccinium caesariense
- Vaccinium corymbosum
- Vaccinium darrowii
- Vaccinium elliottii
- Vaccinium formosum
- Vaccinium fuscatum
- Vaccinium hirsutum
- Vaccinium myrsinites
- Vaccinium myrtilloides
- Vaccinium pallidum
- Vaccinium simulatum
- Vaccinium tenellum
- Vaccinium virgatum
- Vaccinium koreanum
- Vaccinium myrtillus
- Vaccinium uliginosum
Distribution
Vaccinium has a mostly circumpolar distribution, with species mainly present in North America, Europe, and Asia. Many commercially available species with English common names including "blueberry" are from North America, particularly Atlantic Canada and the northeastern United States for wild blueberries, and several US states and British Columbia for cultivated blueberries.North American native species of blueberries are grown commercially in the Southern Hemisphere in Australia, New Zealand and South American nations. Vaccinium meridionale is wild-harvested and commonly available locally. Several other wild shrubs of the genus Vaccinium also produce commonly eaten blue berries, such as the predominantly European V. myrtillus and other bilberries, which in many languages have a name that translates to "blueberry" in English.
Cultivation
Blueberries may be cultivated, or they may be picked from semiwild or wild bushes. In North America, the most common cultivated species is V. corymbosum, the northern highbush blueberry. Hybrids of this with other Vaccinium species adapted to southern U.S. climates are known collectively as southern highbush blueberries. Highbush blueberries were first cultivated in New Jersey around the beginning of the 20th century.So-called "wild" blueberries, smaller than cultivated highbush ones, have intense color. V. angustifolium is found from the Atlantic provinces westward to Quebec and southward to Michigan and West Virginia. In some areas, it produces natural "blueberry barrens", where it is the dominant species covering large areas. Several First Nations communities in Ontario are involved in harvesting wild blueberries.
"Wild" has been adopted as a marketing term for harvests of managed native stands of lowbush blueberries. The bushes are not planted or selectively bred, but they are pruned or burned over every two years, and pests are "managed".
Numerous highbush cultivars of blueberries are available, with diversity among them, each having individual qualities. A blueberry breeding program has been established by the USDA-ARS breeding program at Beltsville, Maryland, and Chatsworth, New Jersey. This program began when Frederick Vernon Coville of the USDA-ARS collaborated with Elizabeth Coleman White of New Jersey. In the early part of the 20th century, White offered pineland residents cash for wild blueberry plants with unusually large fruit. After 1910 Coville began to work on blueberry, and was the first to discover the importance of soil acidity, that blueberries do not self-pollinate, and the effects of cold on blueberries and other plants. In 1911, he began a program of research in conjunction with White, daughter of the owner of the extensive cranberry bogs at Whitesbog in the New Jersey Pine Barrens. His work doubled the size of some strains' fruit, and by 1916, he had succeeded in cultivating blueberries, making them a valuable crop in the Northeastern United States. For this work he received the George Roberts White Medal of Honor from the Massachusetts Horticultural Society.
The rabbiteye blueberry is a southern type of blueberry produced from the Carolinas to the Gulf Coast states. Production of rabbiteye blueberries was a focus in Texas in the early 21st century. Other important species in North America include V. pallidum, the hillside or dryland blueberry. It is native to the eastern U.S., and common in the Appalachians and the Piedmont of the Southeast. Sparkleberry, V. arboreum, is a common wild species on sandy soils in the Southeast.
Successful blueberry cultivation requires attention to soil pH measurements in the acidic range.
Blueberry bushes often require supplemental fertilization, but over-fertilization with nitrogen can damage plant health, as evidenced by nitrogen burn visible on the leaves.
Growing regions
Significant production of highbush blueberries occurs in British Columbia, Maryland, Western Oregon, Michigan, New Jersey, North Carolina, and Washington. The production of southern highbush varieties occurs in California, as varieties originating from University of Florida, Connecticut, New Hampshire, North Carolina State University and Maine have been introduced.Peru, Spain, and Mexico also have significant production, as of 2023.
United States
In 2018, Oregon produced the most cultivated blueberries, recording, an amount slightly exceeding the production by Washington. In descending order of production volume for 2017, other major producers were Georgia, Michigan, New Jersey, California, and North Carolina.Hammonton, New Jersey, claims to be the "Blueberry Capital of the World", with over 80% of New Jersey's cultivated blueberries coming from this town. Every year the town hosts a large festival, which draws thousands of people to celebrate the fruit.
Maine is known for its wild blueberries, but the state's lowbush and highbush blueberries combined account for 10% of all blueberries grown in North America. Some are farmed, but only half of this acreage is harvested each year due to variations in pruning practices. The wild blueberry is the official fruit of Maine.