By every account, blueberry producers are enjoying unprecedented demand. The health benefits attributed to this native North American fruit have earned it a “superfood” designation. Reportedly, blueberries’ high levels of antioxidants lower the risk of cancer and heart disease. Studies also indicate improved memory, balance and coordination.
Consumers’ quest for healthier foods plus the inherent superior preparation ease, storage ability and sweet taste combine to propel predictions of blueberry demand to considerable heights. The North American Highbush Blueberry Council expects U.S. and global production, in particular, to continue its fast pace.
Breeding efforts have made blueberry production possible in areas where none were grown just a few decades ago. Over 30 states now produce blueberry crops. For instance, California concluded that southern highbush blueberries with low chilling requirements perform well in the San Joaquin Valley. Their research also surveyed consumer taste preferences among cultivars, discovering the perceptions of various texture and acid-sweetness balances. The study can be accessed at http://CaliforniaAgriculture.ucop.edu.
Government, industry and university breeders, concentrating on the needs of their area and region, have developed blueberries with enhanced flavor and vigor. Their accomplishments have broadened the fruiting season. Naturipe Foods, which now commands the largest market share in North America, seeks varieties and growing locations to meet the demand for year-round delivery of fresh blueberries.
Traditional blueberry breeding is a slow process, often spanning 10 years. In addition, blueberry plants typically require several years in the field to reach full production potential. Despite these hurdles, new and nearly new cultivars promise better blueberries. The following were available at press time.
ARS extends the season
The USDA Agricultural Research Service’s southern horticultural laboratory in Poplarville, Miss., focuses on the demands of the Gulf Coast. The achievements of Arlan Draper, James Spiers and Stephen Stringer span berry quality, pests and disease resistance. Their most recent cultivar releases include DeSoto, Dixieblue, Gupton and Nativeblue.
Late-season DeSoto, a rabbiteye blueberry, was developed to extend the season for the fresh or processing markets. The flavorful, firm, medium-large berries have a small picking scar. The productive, vigorous plants tend to be smaller than most rabbiteye cultivars. Chilling requirements approximate 500 to 600 hours.
Dixieblue and Gupton, both tasty southern highbush blueberries developed for the early to midseason fresh market, feature firm, light blue berries with small picking scars. The upright, vigorous, productive plants have narrow crowns. Somewhat flat, disc-shaped Dixieblue ripens its medium-sized berries about 10 days to two weeks after Star. Gupton ripens close to 10 days after Star. Its berries are medium-large. While the chilling requirements of both are not precisely known, the breeders indicate both to be about 400 to 500 hours.
With its low-spreading, bushy, mound shape, Nativeblue can also be used to complement southern landscape plantings such as azaleas and crepe myrtles. The small, dark berries have excellent flavor.
University of Florida’s new low-chill cultivars
Blueberry varieties developed at the University of Florida are patented, notes breeder Paul M. Lyrene. Their latest, all southern highbush blueberries, include Farthing, Primadonna, Scintilla, Springhigh and Sweetcrisp.
Farthing ripens at the same time as Star, but yields higher. Its medium to dark blue, large, firm berries have a pleasing flavor and a good scar. In addition, its strong bush has an excellent survival record.
Primadonna ripens about a week earlier than Star. It produces large, high-quality berries. It packs well, and its concentrated set and open cluster habit facilitate harvesting. About 300 hours appears to be the chilling requirement. Management should include measures to ensure adequate leafing. Some locations will require Dormex or winter pruning of Primadonna for maximum performance.
Scintilla has a 200-hour chilling requirement. This vigorous bush produces large, light blue, firm berries with a dry scar that ripen early. It has excellent flavor and exhibits good postharvest storage. Scintilla is recommended for central and north Florida and southeastern Georgia.
Very large, very early ripening, fairly dark berries describe low-chill Springhigh. Most ripen in a three to four-week period, and the open clusters can be harvested rapidly by hand. This upright bush demonstrates unusually vigorous growth and survival in production fields. Springhigh should do well in areas where its flowers can be protected from freezes after the first of February. It leafs out early and well in Gainesville. It has shown good resistance to stem blight and root rot, as well as the leaf disease resistance of other southern highbush cultivars. Yields measure medium to high.
High vigor, excellent survival rate, low chilling requirement plus crisp texture and sweet, low-acid flavor characterize Sweetcrisp. The firm berries, medium blue in color and with a good picking scar, ripen one or two days later than Star. The open clusters and habit make Sweetcrisp a candidate for mechanical harvesting. Rainy weather, however, can cause splitting.
Michigan State’s versatile varieties
The cultivars most recently released by Michigan State University—Aurora, Draper and Liberty—feature vigorous, highbush blueberries with excellent winter hardiness. Breeder James Hancock estimates the chilling requirements at greater than 800 hours. Michigan State’s program strives for improved fruit quality, including balanced flavor, disease resistance, expanded soil adaptation and delayed bloom.
The large berries of the late-season Aurora are light blue, firm and bear a tiny scar. The flavor of this highly productive variety is slightly tart.
Draper’s large, light blue, very firm fruit has a tiny scar and superior shelf life. Plus, it has good flavor. This upright, moderately vigorous bush is widely planted in cold climates. This early midseason, fresh-market variety may be machine harvested.
Liberty produces large, light blue, small-scarred, firm fruit with excellent flavor. The bush is upright and vigorous. Machine harvest may be possible with this very late blueberry.
University of Minnesota cultivars adapt to cold
Superior, introduced by the University of Minnesota, is an exceptional producer in cold climates. It matures the majority of its light to medium blue fruit about a week later than other varieties grown in USDA Hardiness Zones 3 and 4. Similar in size and firmness to Chippewa, the picking scar is similar to Northblue. The flavor is balanced and pleasant, and less acidic than Northblue. In central Minnesota, the plant reaches 4 to 5 feet and spreads 4 to 5 feet as well, but in northern Minnesota, it reaches 2.5 to 3 feet with a 3 to 4-foot spread. University of Minnesota breeder James Luby notes that Superior has been the most productive cultivar in northern Minnesota.
Efforts in other areas
ARS’s Chad Finn, in cooperation with Oregon State, is evaluating grower trials of a new, late-ripening, smaller blueberry with outstanding processing capabilities. A very late-ripening, fresh-market cultivar is also under development.
North Carolina State’s James Ballington has been incorporating the superior traits of wild blueberries into their varieties.
Rutgers Extension blueberry specialist Gary Pavlis says that New Jersey growers desire disease resistance as well as size and flavor. Rutgers breeder Nicholi Vorsa works for those attributes and varieties with machine harvest adaptability. ARS breeder Mark Ehlenfeldt, based in New Jersey, has focused on firmness, plus mummy berry and anthracnose fruit rot resistance. He, along with other researchers, has developed two pink-fruited blueberries, highly prized by landscapers, as well as other varieties in cultivation.
While southern highbush cultivars fit southern regions, and northern areas require northern highbush and half highbush varieties, Maine excels in lowbush, wild blueberries. University of Maine blueberry specialist David Yarborough explains their efforts, “In Maine, we’re taking a different approach than a breeding program. Through improved management of the wild blueberry stands, we’re optimizing the return from the natural resource.” This includes fertility and weed reduction, bee imports and irrigation.
Along with those already mentioned, John Clark, University of Arkansas; Courtney Weber and Marvin Pritts, Cornell; Jennifer Johnson-Cicalese, Rutgers; Kim Lewers, ARS, Beltsville; Mike DeGrandchamp, DeGrandchamp’s Blueberry Farm; Randy Grover, Grover’s Blueberries; Dan Hartmann, Hartmann’s Plant Company; Elizabeth Waters, Waters Blueberry Farm; and the Washington Blueberry Commission provided information for this column.
The author is a writer-researcher specializing in agriculture. She currently resides in central Pennsylvania.