Cranberries don't grow underwater; farmers flood the beds only at harvest
Those photos of farmers wading through seas of floating red berries give a misleading impression. Cranberry beds are not kept flooded; through the growing season they are simply irrigated. Growers flood them in autumn so harvesters can knock the fruit loose to bob to the surface, and again in winter to shield the vines from frost.
Cranberries are evergreen dwarf shrubs or trailing vines in the Vaccinium genus, relatives of blueberries and bilberries, native to acidic bogs across the cooler Northern Hemisphere. The stems creep up to 2 metres but rise only 5 to 20 centimetres. Bees pollinate the dark pink flowers, whose petals fold sharply back. The berries start pale green, redden as they ripen and taste sour enough to drown their sweetness. German and Dutch settlers in New England thought the flower resembled a crane's neck, head and bill, hence the name, which the missionary John Eliot first used in English in 1647.
Henry Hall, a Revolutionary War veteran, began farming them at Dennis on Cape Cod around 1816 and was soon shipping to New York, Boston and Europe. Modern beds sit on uplands with a shallow water table, surrounded by dykes, layered with clean sand and laser-levelled. On frozen winter floods in places like Wisconsin, trucks drive out over the ice to spread fresh sand every three to five years, which curbs pests and revives the vines. Picking-time berries float, so they can be corralled and pumped out; harvesting them while still white produces white cranberry juice. The 5 to 10 percent picked dry bruise less and can be sold fresh.
Breeders first chased resistance to the leafhopper that spreads false blossom disease in the 1920s, then switched to yield once pesticides arrived. Tighter pesticide rules have renewed interest in toughness. Most of the crop's insect pests are native North Americans.
World output in 2024 reached 621,495 tonnes, with the United States and Canada growing 99 percent between them; Wisconsin and Quebec lead. Most berries become juice, sauce and dried fruit, which may be sweetened with added sugar up to 17 times the natural content. Large amounts of juice can intensify the blood-thinning effect of warfarin.
Source: Cranberry
