One of the few fruits native to North America, cranberries were first harvested by the continent’s Indigenous people and are today a staple of Thanksgiving. But like many other crops to which we have become accustomed, cranberries are subject to the harmful effects of climate change.
“More extreme and hotter weather is expected with climate change, which poses challenges for current cranberry production regions. Cranberries are sensitive to heat stress, leading to declines in yield and fruit quality and increases in disease pressure,” the U.S. Department of Agriculture, which is working to make cranberry farming more resilient, says on its website.
Not unlike wine grapes, cranberries, which are harvested in the autumn, need cool evenings to properly ripen, according to Hilary Sandler, a cranberry expert at the University of Massachusetts. But those cool evenings now come much later in the year, which means the fruit endures warmer temperatures for several more weeks than in previous years. “The longer the fruit are on the vine, the more rot you’re going to get. So, it’s always a very anxious time,” Sandler told public radio station CAI.
Waiting to pick cranberries until October or November also means they can succumb to an early frost. “Frost is the number one killer of hopes and dreams,” cranberry grower Iain Ward told The Washington Post in 2020.
Thanksgiving cranberries most likely come from Wisconsin, Massachusetts, New Jersey, Washington State or Oregon; together, these states have made the U.S. the world’s top cranberry producer. According to the Agricultural Marketing Resource Center, in 2021, the U.S. harvested 697 million pounds of cranberries, a haul worth $272 million.
As global temperatures continue to rise due to the burning of fossil fuels and other human-caused factors, cranberry farms will likely need to relocate further north. “The sort of joke is that Massachusetts is going to become the new New Jersey,” UMASS’s Sandler told Ambrook Research. “What does that mean for New Jersey? I don’t know.”