Blueberries: Highbush, Rabbit Eye, and Lowbush
The Blueberry belongs to the Ericaceae family, subfamily Vacciniaceae. Blueberries are found in many areas of the world but gained greatest acceptance in the United States and Canada, the true blueberries belong to the ancient genus Vaccinium, subgenus Cyanococcus.
The blubbery has specific requirements regarding climate and soil. The blueberry is a many seed berry with small, soft seeds that allows it to be accepted by consumers who do not find the seeds objectionable. After reaching its permanent color, the blueberry changes little in size and continues to improve in flavor and sweetness.
There are both wild and cultivated blueberry species. Blueberry varieties originate form hybridization and breeding of native wild species. Blueberry varieties are classified as early, early midseason, midseason, late midseason and late season according to time of maturity. The cultivated blueberries are highbush and rabbiteye. The blueberry harvested commercially but not cultivated in the lowbush.
Highbush Blueberry
The highbush blueberry (Vaccinium corymbosum and Vaccinium australe) range in height from 1.5 to 7 m (5 to 23 ft) and like sunny, acidic areas with a pH between 4 and 5. These blueberries are shallow-rooted plants and are characterized by the lack of root hairs. These fine, fibrous roots require an open, porous soil for ease of growth. Blueberry roosts are associated with mycorrhizal fungi in the soil that aid the plant in nutrient absorption. These blueberries usually require 6 to 8 years to reach full production. Fruit for use in the fresh market is hand harvested while machine harvested fruit goes mainly to the processing market. Major production areas are Michigan, New Jersey, North Carolina, Arkansas, Washington, Oregon, British Colombia, Canada, Europe, New Zealand and Australia.
Rabbiteye Blueberry
The rabbiteye blueberry (Vaccinium ashei) can attain heights of approximately 10 m (33 ft) and are extremely vigorous, productive types with fruit similar to the of highbush cultivars. Rabbiteyes are not winter hardy, but are drought tolerant. In the United States they are grown primarily in the southeastern areas. It has a short of chilling requirement, tolerant to a relatively wide soil pH range and high temperature. Results suggest fertilization and fruit set of pollinated rabbiteye blueberries can greatly impaired by even mild freezes (-1 to -2 degree C), whereas, appropriately timed application of gibberallic acid can result in little reduction in fruit set even after m0derate freezers (-3 to – 4 degree C) of blueberries during bloom. This fruit can be hand or machine harvested.
Lowbush Blueberry
The lowbush blueberries (Vaccinium angustifolium and Vaccinium myrtilloides) seldom grown higher than 0.5 (1.5 ft). They are from native stands and low growing shrubs that spread by underground stems (rhizomes). Shoots develop from buds on the rhizomes, the roots develop adventitiously and form a dense mat. These species are natives to the northeastern United States and Canada, and most of their fruit is harvested from managed, wild stands. Most lowbush blueberry stands that are commercially harvested are under a 2 year cycle of management where the fields are burned every second year to increase fruit production. One year wood from rhizomes gives a greater yield than 1 year old wood from 2 year old wood because more buds are produced. In a wild stand, 40 to 60 shoots per square meter are desirable to give a yield of approximately 1.5 tons per acre. Lowbush blueberries are insect pollinated. Because lowbush blueberries are highly self-sterile, it is essential that pollen form one plant should be available to pollinate flowers of a different genotype. Harvesting begins when 90% of the fruit is blue in color. The fruit is harvested by a specially designed rake that is combed through shrubs to separate out of the fruit. Almost all the fruit is for processing purposes.
Blueberries: Highbush, Rabbit Eye, and Lowbush
