A new report on Massachusetts kelp farming, released September 16 by the National Seaweed Hub, a Connecticut Sea Grant program at the University of Connecticut, delivers a blunt verdict: sugar kelp can be grown in the state’s waters, but almost nobody has found a way to make money doing it. The report was prepared by Joshua Reitsma, Rachel Hutchinson, and Abigail Archer of Cape Cod Cooperative Extension along with Anoushka Concepcion, Sawyer Ohman, Melissa Sanderson, Scott Lindell, and Daniel Gossard, drawing on the Woods Hole Oceanographic Institution, the Global Seaweed Coalition, and the Cape Cod Commercial Fishermen’s Alliance, with support from the Commonwealth of Massachusetts. The researchers interviewed ten Massachusetts sugar kelp growers; by the time the report came out, only one was still actively farming kelp, with most others having walked away within two to four seasons.
Part of the problem is biological, and it splits sharply by geography. North of Cape Cod, waters carry enough dissolved nitrogen, generally 5 to 10-plus micromoles, close to the roughly 10 micromoles kelp needs to thrive, to grow fronds 6 to 8 feet long and yield up to about a pound of kelp per foot of grow line. South of Cape Cod, nutrient-poor water (often below 2 micromoles) produced fronds as short as 2 inches and rarely longer than 4 feet, with yields of half a pound per foot or less. For comparison, Maine, the country’s leading kelp-farming state, sees a median yield around 4 pounds per foot, and the report puts the break-even point for a farm to turn a profit at roughly 2.7 pounds per foot. Even the better-performing waters north of Cape Cod fall short of that line.
But growers told researchers the bigger obstacle wasn’t the kelp itself, it was finding anyone to buy it. “There’s no market, a dead end,” one grower said; another described dumping unsold, unprocessed kelp because there was nowhere to send it. Processing infrastructure is essentially absent in the state, so growers who wanted to dry or otherwise turn their harvest into something sellable had to improvise it themselves, and the report notes that scaling up to real processing means becoming “a whole different business model,” one that requires a Board of Health-approved facility and employees most small kelp operations don’t have. Permitting, notably, wasn’t the barrier people often assume it is; growers called the approval process “not overly burdensome.” The tougher regulatory snag sits farther north, where the vertical lines used to grow kelp raise entanglement concerns for the critically endangered North Atlantic right whale, complicating precisely the sites with the best growing conditions.
The report doesn’t call for giving up on Massachusetts kelp so much as for treating it as unfinished research rather than a ready-made industry. Its recommendations: better site-specific studies before committing new lines to the water, deliberate market-building such as institutional buyers committing to purchase set volumes, investment in shared processing infrastructure, and a look at other species, like dulse, that might suit the state’s marginal, nutrient-poor waters better than sugar kelp does. It also pushes back directly on one of the pitches often made for kelp farming, cautioning that “blue carbon and carbon credits should not be treated as a dependable revenue stream.” For a crop often promoted as an easy win for coastal economies and climate goals alike, the report is a reminder that biology working out is only half the equation.
Further reading: Reitsma, J., Hutchinson, R., Archer, A. et al., “Massachusetts Kelp Cultivation Report,” National Seaweed Hub / Cape Cod Cooperative Extension (2026); Zachary Gordon, “New report examines the kelp industry in Massachusetts,” National Seaweed Hub, University of Connecticut (2026).