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Queen of the Low Tide

With seaweed’s popularity soaring, it’s a good time to be a coastal forager like Heidi Herrmann.


Coast to table: Heidi Herrmann has seaweeding down to a science.

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Heidi Herrmann.

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Herrmann and her band of volunteers hike into and out of remote beaches, carrying their haul in backpacks.

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After harvesting seaweed, Herrmann triple washes it before hanging it out to dry.

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It takes only a few hours for 100 pounds of seaweed to wither to 10 pounds. When it’s ready, Herrmann bags and stores it for delivery.

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A few times a year, the moon’s gravity tugs strongly enough on the ocean’s surface to expose vast expanses of beach and reef usually hidden underwater. When these so-called minus tides occur on Sonoma County’s rocky coast during the spring and summer, Heidi Herrmann is there.

Herrmann is a commercial seaweed forager, and this time of year, when the seaweed is growing and in prime condition, is her high season. A lanky woman with an easy smile, Herrmann owns Healdsburg’s Strong Arm Farm with her partner, Scott Knippelmeir. She grows cut flowers, medicinal plants, and vegetables on the two-and-a-half-acre organic farm, but when spring arrives, her mind is on tide tables.

“When I see a number like ‘-1.6’ in the tide book, I’m like, ‘Oh my gosh,’” she says. “I almost gasp. The ocean is giving us an opportunity to see what’s underwater without any gear—it just takes the effort of waking up early.”

Herrmann was a farmer before she was a seaweed forager; she’s been running Strong Arm Farm since 2009. Her interest in farming started early: Growing up in Los Altos, she spent weekends at her family’s 20-acre apple orchard in San Juan Bautista. But she’s long had an affinity for seaweed. Before she went pro, she says, “I had been collecting seaweed with friends for fun, one day a year. It was just a way to interact with that part of the county and build our sense of place. We’d collect a bagful, and that was enough for me for the year.”

That changed a few years ago when, as a vendor at Sonoma County’s Occidental Bohemian Farmers Market, Herrmann realized her early-season offerings looked a little thin. When she asked herself what she could sell that wasn’t already being sold, seaweed was the immediate answer—and, she soon discovered, an immediate hit. “People were excited and curious to eat local foods and didn’t know that our coast had that,” she recalls.

Today Herrmann remains one of very few commercial foragers in Sonoma County. Hers is a relatively rare breed in Northern California: San Francisco and Marin Counties don’t have great seaweed habitat, though Mendocino County has a long history of harvesting. “There are a lot of old-timers up there,” Herrmann says. “They’re real pioneers in the field. I’ve been able to ask them questions; there’s good camaraderie.”

Though their relatively small numbers suggest otherwise, it’s a good time to be a seaweed forager. In this era of superfood marketing, seaweed enjoys an increasingly lucrative reputation as a nutritional gold mine, high in omega-3 fatty acids, essential minerals, vitamin C, and anti-inflammatory, -bacterial, and -viral properties. Food Navigator-USA, a food industry news site, reported that seaweed-snack sales grew by between $250 million and $500 million in 2014, a number that’s hard to pin down because of bulk sales to Asian markets. But even at the low end, those figures mean that seaweed snacks have outstripped kale snacks. And they’re buttressed by the Specialty Food Association’s 2016 “Trend Forecast” report, which declared that seaweed is “set to explode thanks to its sustainability angle and umami appeal.”

But things like umami appeal are not what get Herrmann out of bed before dawn, ready to take advantage of the low tide. Early in the morning, she says, the coast is both magical and vaguely threatening, like a place “where you’re really not supposed to be; it’s not a human environment.” Much of the slippery, iridescent seaweed that she and her small band of volunteers harvest for two or three hours each morning goes to a short but reverent list of chefs at places like Dry Creek Kitchen, J Vineyards & Winery, the Perennial, State Bird Provisions, and the Progress.

Stuart Brioza, chef and co-owner of State Bird and the Progress, is Herrmann’s biggest customer. Seaweed, particularly nori, has become a key ingredient in his cooking. “I don’t know where my cuisine would be over the past 10 years without nori,” he says. His uses for it are legion: He’s soaked it in water overnight to create a “cold brew” that forms the basis of an avocado sauce, and he’s pickled it for mignonette to spoon over oysters. Brioza’s favorite application may be a salsa verde served with a beef-and-smashed-potato dish. “It’s everything you never knew you wanted,” the chef says. “I keep discovering new flavors.”

When she goes on her first foray of the season, typically in May, Herrmann doesn’t know what she’ll find. “What’s different? What’s new? What’s abundant? What’s taken off?” she asks un-rhetorically. “I have a lot of questions.”

Last year, nori was abundant, but wakame, a long, red-leafed sea vegetable, was harder to find. Herrmann also gathers kombu, iodine-rich bladderwrack, and sea palm. She doesn’t harvest bullwhip kelp, a species with a long, tubelike stalk and a bulbous end. Sadly, the towering algae and the vibrant kelp forests it creates have been decimated, in part by voracious, seaweed-gobbling purple urchins.

The remote, unmarked beaches near Jenner are Herrmann’s favorite foraging grounds. She and her crew descend steep trails to see what the watery gardens below will offer. They move slowly, their heads down as they pick their way across the ephemeral marine landscape before the moon pulls the water over what it briefly laid bare. “There’s this excitement of tide pooling,” Herrmann says. “Everyone in the group is marveling over something or another. There’s just this giddy new-frontier factor of the unknown, of the coast. It’s kind of like Easter, finding these gems all over, but it takes a careful eye.”

It’s an experience she loves to share with others. In June, she’s presenting a seaweed workshop and foray at Fort Ross; in July, she’ll lead an event with ForageSF and Hipcamp that will combine camping, a seaweed talk, and a day of foraging.

Herrmann and her crew typically spend all morning navigating slippery rocks and bagging seaweed, then stuff their dripping loads into seasalt-crusted backpacks, mule up the dirt path, and return to Healdsburg. At her farm, Herrmann triple rinses the crop and drapes it over screens to dry in the sun. In just a few hours, 100 pounds of wet seaweed will wither and crisp to 10 pounds, ready to be bagged and stored for delivery.

Herrmann tries to eat seaweed daily. She’ll drop a piece of kombu into stews or a pot of beans, or powder nori and sprinkle it on popcorn or scrambled eggs. But gathering a wild food and sharing it is what Herrmann loves most about seaweed foraging, something she says connects her with hunter-gatherers throughout history.

“When I’m out there, I could be of any culture or any age,” she says. “I’m collecting food. It just strikes a timeless chord.”

Originally published in the June issue of
San Francisco

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