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Maine’s sea kelp farmers ride a rising tide

It’s a sunny October day, and Paul Dobbins is getting a bit of a late start setting out his seaweed lines. He has been monitoring the water temperature at his lease site, in sheltered ocean water off southern Maine, and it has finally dropped to optimal conditions. Tomorrow he will start setting out thousands of feet of line seeded with millions of tiny sugar kelps, a type of edible seaweed — or sea vegetable, as many prefer to call it — native to Maine.

Paul Dobbins works the spring harvest in Casco Bay, Maine.

Too bad tomorrow’s forecast calls for cold weather and rain, but that’s the way it goes when you work on the water. “It makes you appreciate coming home and taking a hot shower,” laughs Dobbins, an affable guy suited up in fleece and jeans, seemingly unaware of the chilly breeze as he zips us to one of his lease sites, 15 minutes from the South Portland waterfront in the waters off Little Chebeague Island, in an open inflatable.

Dobbins is co-owner of Ocean Approved, said to be the nation’s first commercially successful kelp farm and a leader among Maine interests working to get this nascent industry off the ground. Dobbins will be on the water throughout the winter, checking on his plants and setting new seed strings, during a season that runs from autumn to spring. He’ll have to clear his inflatable of snow and watch out for storms and ice, which could cause his lines to cross and chafe off the tender plants growing there.

Not that the life of a seaweed farmer is all that arduous. And that’s part of the industry’s appeal, Dobbins says. “We’ll spend tomorrow and Friday seeding, and we’ll be out here two hours each day, then another five hours the following week, and the whole farm will be seeded in,” he says. “The heavy work starts in March, when we start to harvest. We’ve demonstrated that two people in half a day can harvest 10,000 pounds, so that’s efficient also.”

The sea-farming cycle actually starts in a nursery. At the marine lab of the Southern Maine Community College campus, Dobbins keeps six fish tanks — the type in which a child might house a pet iguana. Each holds a dozen 15-inch sections of 2-inch PVC pipe, stood vertically, neatly wrapped with 200 feet of what’s essentially kite string, and soaked in a saltwater solution. The string is covered with kelp spores — millions of microscopic edible seaweeds that have begun to grow to various degrees of visibility. The 30,000 feet of seed string will be threaded onto 20,000 feet of lines strung between moorings on two compact lease sites in Casco Bay.

“We essentially build the farms every seeding season,” says Dobbins. Here, within the sights and sounds typical of any Maine bay — lobster boats roaming among trap buoys, seals surfacing, gulls overhead, ferries motoring by — they’ll continue to grow, competing for space, for three months, until just a couple of dozen per foot reach lengths of 10 to 14 feet. Then the kelp will be harvested, processed and sold, and cooks will use it for salads, soups, stir-frys, sushi-style wraps, even smoothies.

Dobbins got into seaweed farming when he realized that his career in biotechnology, which involved extensive travel, took him too frequently from his children. He loved being on the water, so he looked for marine-related opportunities. “This was the one that had the most potential. It’s also a lot of fun,” he says.

He dove into the field, visiting sites overseas, pulling in knowledge from all over the world, adapting it for New England waters, obtaining grants to develop farming and processing techniques, and partnering with researchers in Maine and elsewhere. In turn, he freely shares his knowledge. Indeed, he has made a point of “dumbing down” the technology, so to speak, so that anyone can create a nursery and farm.

Cultivated kelp will make its way to restaurants across the country.

“If you’ve got a boat, it’s, ‘Hello, kelp farm,’ ” says Dobbins. “Everything you need to create a nursery and a farm can be purchased at a big-box store, a Petco and a marine store. The only thing that can’t be purchased there is a microscope” — to track biological parameters — “and the seawater.”

Ocean Approved started as a harvester of wild seaweed, began farm trials in 2009 and now farms about half of its product, with the goal of moving entirely into cultivation. It had its first commercial crop in 2013. Last May, the company harvested 28,000 pounds of mainly sugar kelp, along with horsetail kelp and alaria.

The product goes to the company’s small processing facility to be rinsed, trimmed, blanched, flash-frozen and packaged. Then it’s sold to restaurants and wholesalers. Buyers include hospitals, universities and restaurants, the latter ranging from the Flatbread Company, a Maine-based chain that uses kelp on its pizza, to Dan Barber’s white-linen Blue Hill restaurant in Manhattan.

Naturally, the prospect of sampling other edible seaweeds is irresistible. Since Dobbins’ seaweeds aren’t ready, I visit Sarah Redmond, a Maine Sea Grant marine extension associate based at the University of Maine’s Center for Cooperative Aquaculture Research, in Franklin. With University of Maine professor Susan Brawley, Redmond has been instrumental in giving the industry its start through her studies of farming techniques in relation to various species. “Each species is very different,” she says. “You have to figure out what you can get on the farm, when it’s ready, what’s the best way to handle it, and what kind of product you want to turn it into.”

Redmond pulls out zip-close bags full of edible seaweeds. First there’s wild-harvested sugar kelp, with a heavy coat of white powder that’s a mix of naturally occurring salt and sugar. It’s mahogany in color, thick and hearty. Then there’s farmed sugar kelp, still green and more delicate in feel, younger than the wild product. The taste of both is dulcet, the farmed kelp slightly crunchy, the wild variety chewy.

Redmond pulls out another type of sugar kelp known as “skinny kelp,” so called for the narrowness of its fronds. It has a bit of a citrus flavor, and its texture is a bit tougher. Alaria is rich in mineral flavor, melting quickly in the mouth, with a slightly fishy aftertaste.

Redmond opens a jar of pickles she makes with the stipes — similar to a plant stem — of baby sugar kelp. They taste like dilly beans, with a briny note. She also keeps handy a container of ground sugar kelp to throw on her food. “I make grilled cheese and seaweed a lot,” she says.

The idea of sea vegetables might seem odd to Americans, although many are accustomed to the use of nori to make sushi. But the food is popular elsewhere around the world. The Maine coast is rumbling with activity in farmed sea vegetables, poised to take off as a player in a global seaweed industry worth $5.5 billion to $6 billion a year, according to the Food and Agriculture Organization of the United Nations. Seaweed for human consumption, which goes back more than 1,000 years in Asia, represents about $5 billion of that total. Hydrocolloid extracts, used for gels and thickeners, along with other uses, such as fertilizers and animal feed additives, make up the rest. Globally, more than 90 percent of that seaweed — 21 million metric tons — is harvested from cultivated crops, and the rest is from the wild. The farming of seaweed has expanded rapidly as demand outstrips the supply available from natural resources, the FAO says.

Maine has a wild-harvest seaweed fishery going back 50 years and operating on a relatively small scale. Rockweed makes up about 90 percent of Maine’s seaweed landings, going for such non-food uses as nutritional supplements for animals and people, and fertilizers.

On a parallel track, aquaculture researchers in Maine have been studying seaweed cultivation for more than a decade, with various ideas in mind. One is that it would be a great supplement to the wild fishery, especially as demand rises and the wild harvest falls short. Another is that seaweed cultivation integrates well with established aquaculture enterprises, such as shellfish farms. And there’s some thought that seaweed farming — a winter occupation, relatively inexpensive, easy to set up and requiring little tending — would make an excellent supplemental income for lobster fishermen and others. Seaweed farming is thought of as an ocean “restorative” that takes up excess carbon and nutrients and provides nurseries and protection for marine organisms. And it doesn’t require the land, fresh water and other inputs seen in terrestrial farming.

Sarah Redmond, a Maine Sea Grant marine extensions associate, checks incubating seed strings.

The primary focus has settled on sugar kelp, named for the sweetness of its fronds, since it is a fast-growing Maine native with established success in producing seedlings. Other seaweeds of interest are the heartier horsetail kelp; alaria, also called winged kelp; skinny kelp; and gracilaria, dulse and laver.

Farther east along the coast — within sight of the home of aquaculture pioneer Ed Myers, who established Maine’s first mussel farm in Clark’s Cove, off Walpole, in the 1970s — the founders of Maine Fresh Sea Farms expect to have similar success. Peter Arnold, Seth Barker and Peter Fisher bring together the skills of a sustainability expert, marine biologist and seafood salesman, respectively. Five years ago, they began experimenting with a few lines, then obtained federal grants to ramp up to a Phase I trial in 2014, and now to Phase II commercial production.

Using a corner of the nearby University of Maine’s Darling Marine Center to incubate seeded string, they have about 3,500 feet of line out at their primary site, where they expect this year to harvest 20,000 pounds of primarily sugar kelp, with some alaria and dulse. Their plan is to double the harvest for each of the following two years. And they’re experimenting with another type of “sea green” called gracilaria at a separate site. Their goal is to identify a mix of native species that will extend the growing season year-round.

The farm is about a stone’s throw from the dock in sheltered water. Barker and Arnold hop into a beat-up outboard and zip over to the telltale line of mooring balls. With a grappling hook, Barker lifts a line partway out of the water. It’s covered with baby kelp plants that are securely connected by a stalked organ appropriately called the “holdfast.”

“The frilly edge is characteristic of kelp,” Barker says, plucking off a small leaf. “These look like they’re getting a good start.”

The plants need to grow quickly and strongly enough to outcompete less-desirable algae, called diatoms. In the winter, the plants build up a nutrient reserve that allows them to explode with growth in the spring. “It will be probably December before we have a sense of what our crop will be,” says Barker. “Then we’ll have the winter and the spring growing period, which is really important. That’s make-or-break time.”

As know-how spreads, the biggest challenge facing this nascent industry is the lack of infrastructure for processing and marketing. “What happens is, everything is ready at the same time,” says Redmond. “It’s like any food production. We have a field full of food that needs to be processed all at once. If there’s no place to bring it to get processed, what are you going to do?”

Redmond has been working with Ocean Approved, Maine Fresh and Maine Coast Sea Vegetables. The third is a longtime harvester/processor of wild seaweed, in recent years looking to add farmed product as the wild harvest falls short of consumer demand. Redmond is also working with shellfish farmers interested in growing seaweed at their sites. This activity is bolstered by organizations, academia and government agencies providing grants and partnerships. In 2014 the University of Maine, University of New England and other Maine institutions received a five-year, $20 million grant from the National Science Foundation’s Experimental Program to Stimulate Competitive Research to establish a Sustainable Ecological Aquaculture Network in Maine. Among its initiatives, the network is offering demonstration workshops and farms for sea vegetables.

What could be more Maine than a lobster roll? One topped with locally grown sea vegetables.

Michael Lomas, a senior research scientist at the Bigelow Laboratory for Ocean Sciences in East Boothbay, identifies possible challenges for this burgeoning industry, including limited coastal space, a low level of federal/state funding, small companies lacking financial resources for R&D and potential for economy of scale, and overseas competitors that dominate the market. As the former chairman of a Maine Technology Institute-funded advisory group examining the potential for a Maine “algal cluster,” Lomas views this kind of group, which shares technology and ideas to build momentum, as a collaborative solution to move the industry forward on regulatory, financing, R&D and marketing fronts.

Collaboration is what it’s all about for Maine’s sea vegetable interests. And they’re eager to show off the state’s potential. “There’s a lot of energy and interest and enthusiasm around this,” Redmond says. “Other people are watching us take the lead.”

This article originally appeared in the March 2016 issue.