Duke blueberry of Northern Highbush

New Jersey is the largest fresh market blueberry supplier in the United States. One of the major varieties of blueberry grown in the state is Duke, named for Duke Galleta, one of the founders of the Atlantic Blueberry Company in Hammonton, New Jersey.

Vaccinium Duke or Blueberry 'Duke' is a popular Northern Highbush. It is a proven performer over a large region of the country. One the best characteristics of 'Duke', is late bloom followed by early ripening.

Best grown in acidic (pH of 4.8 to 5.2), peaty, organically rich, medium to wet, well-drained soils in full sun to part shade. Shallow, fibrous roots need constant moisture and good drainage. Plants appreciate good organic mulch.

‘Duke’ had the highest percentage of fruit buds, averaging 63.5% compared to 58.1% and 45% in ‘Elliot’ and ‘Bluecrop’.

Plantings of Duke blueberry also found in Canada, Australia, and New Zealand, France the Netherlands, Germany, Spain and northern European countries and in Chile.
Duke blueberry of Northern Highbush

What are blueberries good for?

Blueberries (family, Ericaceae; genus, Vaccinium) are indigenous to North America. The Vaccinium genus consists of many species, which have edible fruits.

Like bilberry (V. myrtillus), cranberry (V. macrocarpon), lingonberry (V. oxycoccus), and huckleberry (V. ovatum and V. vaccillans), blueberries are valued fruits.

Native American enjoyed fresh blueberries and also dried them for use with other foods. They are believed to use blueberry roots and leaves as medicine.

A tea made from blueberry leaves was considered good for blood and blueberry juice was used to treat cough.

These early insights and experiences about health benefits of blueberries are now being corroborated. Experts showed that blueberry leaves have higher phenolic and antioxidants values than the fruit tissues. In laboratory studies, dried extract of blueberries having high antioxidants reversed signs of aging.

Other studies have shown that specific wild blueberry extracts may have anti-adhesion and chemopreventive properties.

Thus, the blueberries are emerging as a functional fruit for improving health and quality of life.
What are blueberries good for?

Blueberry may keep cancer away

The blueberry is becoming widely recognized for its health benefits. Blubbery is one of the richest source of anthocyanins that are antioxidant and anti-inflammatory. Inflammation and Parkinson stress are involved in virtually every major killer disease: Alzheimer’s, Parkinson’s, diabetes and heart disease.

There is a very strong evidence that the consumption of anthocyanins reduces the risk of heart disease, cancer and other problems related to aging.

Berry anthocyanins anti-carcinogenic properties appear to stem from their ability to affect multiple mechanisms, including inhibition of cancer promoted enzyme and blocking of activation of cancer growth. 

Blueberry phytochemicals inhibit growth and metastatic potential of breast cancer through modulation of the phosphatidylinositol 3-kinase pathway.

Blueberry also found to inhibit colon cancer cell proliferation and induce cell death. It reduce androgen-dependent growth in prostate cancer cells.

To date anticancer mechanisms suggested for blueberry phytochemicals include:
*Induction of enzymes involved in the detoxification of carcinogens
*Promotion of programmed cell death
*Inhibition of enzymes involved in metastasis

A University of Illinois study, found that wild blueberry showed the greatest anticancer activity.
Blueberry may keep cancer away

Anthocyanins in blueberry

Total anthocyanins in blueberry fruit range from 85 to 270 mg per 100g. In chemical structure, anthocyanins consists of an aglycone, the anthocyanins, linked to a sugar moiety.

The anthocyanins are a group of a water-soluble plant pigments that are usually dissolved in the cell fluids, rather than in the lipoidal bodies.

Anthocyanins are natural colorants belonging to the flavonoid family and are widely distributed in fruit. They often responsible for the blue, red or purple pigment found in fruits and plants.

Generally, anthocyanins have antioxidants properties, which could protect and enhance out body systems with bioactive abilities such as the immuno, anticancer, antimicrobial potencies and others.

The health function of anthocyanins in preventing obesity and diabetes were also reported.

The six most frequently found aglycones in fruits and berries are delphinidin, cyanidin, petunidin, pelargonidin, peonidin and malvidin. Blueberry contains five major anthocyanins: glycosides of cyanidin – 7.7%, delphinidin – 31.2%, peonidin – 18.6%, petunidin 8.8%, and malvidin 33.8%.
Anthocyanins in blueberry

Fruit of Blueberries in North America

Blueberries grow wild in many parts of the world. Blueberries are mainly important in Canada and the USA.

Other producers include the countries of Scandinavia and eastern Europe. In recent years there has been increased planting in New Zealand, France and UK.

North America farmers grow over 103 million pounds of blueberries a year. Canada and United States supply almost 95% of the total blueberries for the food industry.

Cultivation highbush harvesting begins in the spring in the southern United States and continues in Nova Scotia and British Columbia into October.

Cultivated blueberries grow in clusters and the berries do not ripen all at once. The berries at the bottom of the cluster may be ripe, while the ones on top are still green.

Highbush berries are grown in British Columbia and on much smaller scale in Ontario, Quebec and the Maritimes.

Canada is top wild blueberry producer in the world, while Nova Scotia contributes one-quarter of the total amount.

Domestic and international demand for berries is on the rise with increased public awareness of the many health benefits associated with berry consumption, including high fiber content and antioxidant activity.

Canada acreage of cultivated berries has more than double in western Canada during the past decade.

British Columbia is the largest blueberry producer in Canada, About 60 to 70 percent of the blueberries sold in North America are cultivated.

Half of the commercial blueberries are turned into jams, pies and other bakery products and processed food.
Fruit of Blueberries in North America

Ancient Blueberries

This berry has several names – whortleberry, bilberry, hurtleberry and cousins – saskatoons and huckleberry.

Many botanists believe a blueberry antecedent could be the most ancient living thing on earth, stepping up to the cereal bowl at the whopping 13,00 years old.

Primitive man was a hunter and a collector and one of the things they liked collecting were berries. Blueberries being chock full of antioxidants and nutrients, were a chief sources of nutrition for many ancient civilizations.

During the times of the Greeks and Romans, blueberry relatives were an important part of the daily diet.

The harvest time of blueberries since ancient times has been a time of celebration.

Indian in North America have gathered the fruit for centuries an still continues considerably to the harvest. It was them who introduced the practice of burning to control encroaching shrubs, trees and other unwanted ‘weeds’ and to kill the pests and diseases that invade the blueberry patches.

The Indians who lived on the sores of what is now called Lake Huron mixed powdered, dried berries with water, cornmeal and wild honey to make pudding, reported by observer and explorer in the early 17th century.
Ancient Blueberries

Fruit of Blueberry

The genus Vaccinium L. includes approximately 400 species, which are concentrated in the montane tropics but extend to all continents except Australia.

It is a high value crop which can thrive on acidic, imperfectly drained sandy soils, once conspired worthless for agriculture crop production.

Blueberry fruits are round and slightly flattened in shape. Blueberries have small, mostly elliptic, short stalked leaves.

They have a crown like structure on the calyx end (bottom) of the fruit and a depressed ring on the top of the fruit where the stem was attached.

The skin is smooth and soft and ranges from light blue to dark blue, often with a grayish cast. Blueberries are small, usually around 1/2 inch in diameter.

Blueberry has been domesticated most recently, having been accomplished entirely within the 20th century.

Wild lowbush blueberry plants were probably the first blueberries to be cultivated with native North Americans burning the heaths to increase.
Fruit of Blueberry

Culture of Blueberry

Culture of Blueberry
Blueberry are deciduous shrubs ranging in height from 1’ for lowbush blueberries (Vaccinium angustifolium) to 6’ for highbush blueberries (V. corymbosum) to over 30’ for rabbiteye blueberries (V. ashei).

The flowers look like dainty white bells and appear in spring on shoots that grew the previous season.

Blueberries are hard in Zones 3-9, depending on species and cultivar.

Blueberries require full sun and well drained, moisture retentive, acidic soil with a pH of 4.0 – 5.0.

Of the 3 species highbush blueberries are the most finicky about soil.

Blueberries generally grow well in soil enriched with acidic organic material, such as peat moss, composted pine needles or oak leaves or compost made from pine, oak or hemlock bark.

Fertilize with acidic fertilizers, such as cottonseed meal or soybean meal. Blueberries enjoy a thick, organic mulch.

Most blueberries are not wholly self-pollinating. Plant at least 2 different cultivars near each other for adequate cross-pollination.

Prune plants each winter, beginning when bushes are about 4 years old. On highbush and rabbiteye plants, remove drooping or very old braches and thin out branches where growth is too dense.

Cut lowbush plants to the ground every third year for a harvest every 2 out of 3 years.
Culture of Blueberry

Blueberry in Botany

Blueberry
Linnaeus grouped all plants into the plant kingdom Plantae, to separate them from animals. The blueberry is further classed with all plant producing flowers and seeds into the division Spermatophyta. The flower has an ovary, thus placing it in the class Angiospermae, and its seedling has two leaves, putting it in the subclass Dicotyledonae.

It is member of the Ericaceae family of plants comprising mostly woody shrubs that grow naturally on acid soils. This is a large family and is found widely distributed throughout the world. It includes, among others, the rhododendrons, azaleas, heathers, heaths, and mountain laurels.

The blueberry belongs to the subfamily Vacciniaceae; the tribe Vaccinieae; the genus Vaccinium; and the subgenus Cyanococcus (from Greek cyano (‘blue”) and coccus (berry).

There are many species. The terms “genus’ (pl. genera) and “species” are most commonly used when discussing plants horticulturally. The first letter of the genus name is always capitalized; the first letter of the species name is lower case. Both are italicized or underlined. Among growers, species are rarely mentioned, but a more specific term, “cultivar,” is common.

The highbush blueberry ranges from 5 – 23 ft in height. The cultivated highbush blueberry was developed primarily from two species: V. corymbosum L. and V. australe Small, though other species have been utilized in modern breeding programs. The letter, name or abbreviated name following the species refers to the person who first named it (e.g., “L” is the abbreviation for Linnaeus).

Wild plants are distributed in sunny, acidic and swampy areas from Nova Scotia and southern Quebec west to Wisconsin and south to northern Florida and southeastern Alabama. Wild southern populations are comprised primarily of V. australe Small, whereas V. corymbosum L. occurs in more northerly areas. Because of rampant hybridization, these species have intermingled and crossed with a half dozen other economically minor species, thus giving rose to various intermediate forms.
Blueberry

Blueberries

Blueberries
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.

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.

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.

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