Winter Activities on Cranberry Bogs
On a cold winter morning in southeastern Massachusetts, when the ground is covered in snow and the birds have long flown south, something unexpected may be happening just beyond the tree line: small trucks driving across what looks like a frozen lake, growers drilling holes into the ice, and sand being spread across bogs that won’t turn green again until spring.
With more than 11,000 acres of active cranberry bogs in southeastern Massachusetts, these farms are woven into the fabric of the community, with many residents having worked on a bog at some point, or having family members or neighbors who farm. And yet, even for lifelong residents, much of what happens on a cranberry bog—especially in winter—remains a mystery.
Winter is often called the cranberry “off-season,” but that description doesn’t tell the full story.
After harvest wraps up in late October or early November, cranberry vines go dormant. The plants may appear asleep, but they are already carrying next season’s buds and need protection from winter’s harsh conditions. One of the biggest threats is not snow, but wind. Cold, drying winds can damage vines and cause what growers call “winter kill”—essentially frostbite for plants.
To protect against this, many growers flood their bogs in the winter. The water acts as insulation, shielding the vines and buds from extreme cold. It’s not a passive process, either. Growers must regularly monitor the flooded bogs to ensure the plants beneath the ice are still getting enough oxygen.
If winter temperatures stay cold long enough, flooded bogs freeze into thick sheets of ice—several inches deep. That’s when an unusual sight appears: growers driving buggies out onto the ice. This isn’t about living out Zamboni-driver fantasies. It’s called ice sanding, and it’s incredibly important to cranberry farming.
Cranberries grow naturally in sand, and sanding is a long-standing, science-backed farming practice that dates back to birth of the industry in 1816. Recognized as a Best Management Practice by USDA Natural Resources Conservation Service, UMass Cranberry Station, Massachusetts Department of Agriculture (MDAR), Massachusetts Department of Environmental Protection (DEP), and the U.S. Army Corps of Engineers, sanding stimulates new upright growth, suppresses disease, and reduces insect pressure. Every two to five years, growers spread a thin layer—about half an inch to two inches—of sand across producing bogs. Ice sanding is the preferred method, though growers have other options if Mother Nature doesn’t cooperate.
This winter, sanding isn’t the only major activity underway. Nearly two dozen cranberry growers will also be tackling bog renovation projects. In December, MDAR awarded $1.49 million to 21 growers through its Cranberry Renovation & Enhancement Program. The goal is to help revitalize aging bogs, improve productivity, and strengthen environmental stewardship.
Bog renovation is a big job. It involves removing existing vines, leveling the bog, improving drainage and irrigation systems, and laying down at least six inches of fresh sand before replanting with new vines. The payoff is significant. Renovated bogs can produce up to five times more fruit while using similar inputs. They also require less water during the growing season and offer better long-term sustainability.
While some of the work happens out on the bogs, much of winter is spent behind the scenes. Growers catch up on paperwork, attend industry meetings, and take continuing education and certification courses. It’s also prime time for equipment repairs and upgrades.
Unlike many other agricultural industries, cranberry farming relies heavily on custom-built machinery. Large equipment manufacturers don’t make cranberry-specific tools, so growers often design and build their own pickers, pruners, harrows, pump rigs, and other equipment by hand. Ingenuity and problem-solving are as much a part of cranberry farming as water and sand.
So while the bogs may look quiet this time of year, winter as a cranberry grower is anything but slow. It’s a season of protection, preparation, and planning—work that ensures when spring arrives and the vines wake up, the Commonwealth’s No. 1 food crop will be ready for another year.