The blueberry is one of few fruits native to North America. Gathered by Native Americans from bogs and forests, they were consumed fresh or preserved and used for medicinal purposes, or as a dye for baskets and cloth.
Types & Varieties
The most common types of blueberries are Northern highbush, lowbush (wild) and rabbiteye. Northern highbush blueberries are predominant in North America and include many different varieties. Six U.S. states account for most cultivated highbush crops in terms of acreage and commercial production: Michigan, Georgia, Washington, Oregon, New Jersey, and North Carolina. Newer acreage planted in both Florida and California may influence production in years to come.
British Columbia is the top producer of highbush blueberries in Canada. Lowbush or wild blueberries are used in food processing and grown in Maine and eastern Canada.
Blueberry plants perform well in acidic, sandy, well-drained soil. Manual harvesting occurs over the course of three to four weeks as the berries ripen. Mechanical harvesting tends to cause excessive damage; these berries are considered unfit for the fresh market and sold for processing or freezing.
Pests & Diseases
Aphids feed on the undersides of young leaves and tender shoots. The blueberry maggot lays eggs in fruit and larvae feed on the inside of berries. Other pests to look out for include bud mites, caterpillars, cutworms, fruitworms, Japanese beetles, leafhoppers, plum curculios, scale insects, and thrips.
Botrytis (grey mold) and Rhizopus rot is spread easily and are resistent to cold temperatures. Twig blight is a fungal disease that develops in early spring from dead, infected twigs. Other diseases of concern include anthracnose, bacterial wilt, canker, and both scorch and shock viruses.
Storage & Packaging
Blueberries should be cooled within hours of harvest to lower respiration and ripening. A controlled atmosphere with 15 to 20% carbon dioxide and 5 to 10% oxygen reduces mold growth and other decay-causing organisms.
References: Michigan State University Extension, NC State Extension, University of Maine Extension, U.S. Highbush Blueberry Council, USDA.
GRADES & GOOD ARRIVAL
Generally speaking, the percentage of defects shown on a timely government inspection certificate should not exceed the percentage of allowable defects shown, provided: (1) transportation conditions were normal; (2) the USDA or CFIA inspection was timely; and (3) the entire lot was inspected.
|U.S. Grade Standards||Days Since Shipment||% of Defects Allowed||Optimum Transit Temp. (F)|
Canadian good arrival guidelines (unless otherwise noted) are broken down into five parts as follows: maximum percentage of defects, maximum percentage of permanent defects, maximum percentage for any single permanent defect, maximum percentage for any single condition defect, and maximum for decay. Canadian destination guidelines are 8-3*-3-8-3 (*no more than 1% foreign material).
References: DRC, PACA, USDA.