It moves in glassy greens and browns that burn brightly underwater between spears of sunlight, and has a distinct slime that our legs feel before our eyes see. Like it or lump it, seaweed is hard to ignore. Yet few have thought of using it as an alternative material to plastic. Julia Marsh, founder of Sway, is a woman who has thought about nothing else.
Words by Megan Brownrigg
“There’s all these weeks!’ Julia says with a tired smile in her voice while packing.
Sway’s CEO is making time to talk between New York Climate Week and London Design Week, which also doubles as London Packaging Week. Her work sits snugly in the overlap between these three summits. Sway replaces plastic packaging using a material she’s been irrevocably seduced by: seaweed.
For a lot of us, seaweed brings to mind nostalgic childhood squeals of getting tangled in slimy tendrils. For Julia, they are underwater rainforests growing along the earth’s coastlines which have the power to preserve our planet’s biodiversity. There’s seven million square kilometres of seaweed already growing around the world — about the same size as the Amazon rainforest. But contrary to trees, seaweed doesn’t require land, fresh water or fertiliser to grow, and does so 20-30 times faster than land-based agriculture. Julia might be seaweed’s biggest groupie, and it’s hard to argue with her. This runny, sticky algae is wild. It increases biodiversity, sucks up carbon for lunch, and balances the ocean’s water chemistry.
Sway wants to add something else to seaweed’s CV: obliterating the need for plastic packaging. Founder Julia is a designer by trade, but has conservation in her blood. Growing up in the Monterey Bay area of California with her parents, nature was always a constant.
“My mother was an amateur botanist, so as kids we’d go for walks in the forest and my sister and I would be expected to identify all the flowers and plants! My dad was a fisherman in his free time. He’d wake us up early enough every morning before school to take us to the tide pools. At the time it seemed normal but in retrospect that’s insane, being a parent is hard enough!”
During her childhood visits to shore, Julia was lucky enough not to see tides clogged with plastic bottles.
“Monterey Bay is a special place, home to an aquarium, which is the source and centre of a lot of incredible conservation work, and to scientists and researchers who safeguard the sea. So no, I wasn’t exposed to a lot of ocean pollution where I grew up. But I was exposed to pollution in other natural spaces, on hikes and in national parks.” Julia is haunted by the fact that plastic has been found in the world’s most remote places. It pickles soil on top of the Pyrenees, lurks in Arctic sea ice, and sits at the bottom of the Mariana Trench — the deepest place on earth.
While pursuing a career in design, Julia became aware very quickly that making practical things of beauty is problematic if you don’t want them to live on in perpetuity. Like, say, plastic does. With a breakdown rate of anywhere between 100-1000 years, its territorial stain on the planet becomes easier to imagine when you consider that 500 billion plastic bags are still being used worldwide annually. Of course it’s everywhere.
“I realised that a lot of the alternatives to plastic were partial fixes. Agencies would be unwilling to make a switch to them because why would you switch to something more costly, which performs worse, actually doesn’t degrade and still has petroleum in it?”
Julia also noticed that the sourcing side of materials is overlooked. We know the problems that plastic produces, but we rarely look up the oil refinery that it comes from, or the communities that its manufacturing affects. She argues that the same goes for corn, sugarcane, and potato starch: all source materials which are being exploited to create plastic alternatives. Julia’s got a point, and it’s one she isn’t willing to drop. She regularly self-refers as “obsessed” when it comes to her mission to find alternative materials to plastic. I ask her what fans these obsessive flames.
“Twenty years ago we just said ‘responsible’ and ten years ago we said ‘sustainable’. Now we’re embracing regenerative design.”
“We are living in a time when climate should be at the centre of all our work. All the problems that we have to tackle are interlinked. If you care about the plastic problem, you also care about the proliferation of petroleum which feeds the climate crisis, and the climate crisis fuels social inequity and increases our dependence on plastics because they’re the most affordable, accessible, convenient way to package just about anything. And that social inequity feeds the plastic problem. So if you want to solve the plastic problem you have to feed all these interlinked issues and when your work is tied to something so important, you have to be obsessed with the solutions. It’s basically impossible not to be.”
For Julia, the difficult part as a designer is not resisting plastic. It’s creating a system which allows the packaging space to actually abolish it.
“I’m non-technical. I can aspire to create work of consequence, but the actual physical components of innovation in material science is really hard, and takes a long time and you have to be really patient. The most challenging part of this journey is finding people much smarter, in different ways, to me.”
Despite not being a PhD polymer scientist, Julia landed on her favourite material by herself.
“I think the words that we use for how we aim to treat the earth better are constantly evolving. Twenty years ago we just said ‘responsible’ and ten years ago we said ‘sustainable’. Now we’re embracing regenerative design, where all of the work we do actually replenishes the planet rather than sustaining the way that things are. I went on the hunt for a material that fits that criteria.”
One night in a Brooklyn apartment, Julia melted some agar and threw the steaming sea gloop into a set of moulds.
“Seaweed is the epitome. It creates healthier ecosystems by doing all this hard work in the ocean already, and you can extend that impact by using it to replace plastic.”
“You can order seaweed on the internet, there’s recipes for all sorts on there!” she laughs. “I made these really horrible seaweed cups and thought, if I can do this with no technical skill whatsoever, then a scientist can work out what’s actually happening here and optimise it for a larger system.”
Today, Sway’s larger system means that their seaweed packaging will biodegrade in four to six weeks. Cleverly, the product still has a 12-month shelf life. But how does seaweed compare to other materials? Julia says that trees certainly fit the regenerative bill, but they take a long time to grow. She reckons that mushrooms are probably heralded as the most regenerative material because they decompose into healthy, nutrient-rich soil afterwards. But without a doubt, she feels that seaweed is the coolest kid in the gang.
“Seaweed is the epitome. It creates healthier ecosystems by doing all this hard work in the ocean already, and you can extend that impact by using it to replace plastic. Once you put all those things together it’s hard to want to explore anything else.”
To get tangled in seaweed’s smallprint for a moment: it creates habitats for a huge chunk of underwater wildlife, a serious skill set considering that 74% of our world’s wildlife lives underwater. Seaweed also balances the water acidity of our oceans, to the extent that it has been used to clean up polluted areas. This stuff sequesters up to 20 times more carbon per acre than trees, according to one Harvard study. This dancing weed knows how to wiggle.
Still, Julia is open about seaweed’s blurry bits. There are over 12,000 species of this algae and each one’s alchemy will be slightly different, including how long it can store carbon for. While she waits for more research to emerge on this, Julia’s happy to invest in seaweed’s known superpowers, such as how beneficial it is to cultivate.
Digging into the tender subject of farming on an industrial scale, seaweed brings a sigh of relief. It exists in abundance and its cultivation has a carbon sequestration potential of 421 million metric tonnes globally, according to Oceans 2050. There’s also the economic offering for the livelihoods of coastal communities.
“There will be an ecosystem of solutions that solve the plastic problem, and we want that. We want diversity in our solutions.”
“Coastal livelihoods can no longer depend on traditional practices, like fishing, for their income in the climate future which we know is on its way,” says Julia. “Their relationship with the ocean is changing. Seaweed and kelp farming can offer a viable replacement to these ways of life, and enrich our ecosystems rather than damage them.”
The World Bank has projected that seaweed could create 100 million jobs in the blue economy, for its food production alone. Replacing plastic packaging adds another string to that bow of possibility. Julia has travelled the world to partner with seaweed farmers and develop ethical scaling models that could offer them create climate resilient employment.
Another thing that Julia has learned from seaweed, which has stayed fast through moving oceans for billions of years, is to hope and persist without exception.
“I think when the vastness of the climate crisis sets in, it’s very easy to feel discouraged. And when solutions are presented, it’s very easy to feel sceptical, and I think that scepticism is warranted. So I wouldn’t say I’m an unbridled climate optimist, being an optimist doesn’t mean that you’re ignorant to the realities and complexities of the climate crisis. However, I’m really in the depths, or in the weeds you could say, of researching innovation around materials. More so now than ever, really knowing the complexity and vastness of the issue, I do feel hopeful that solutions are on their way. And I think that as long as brands are continually pressured to be honest, whilst investing in the solutions, it’s okay to be a climate optimist.”
Julia’s reasons for hopefulness are compelling and rigorously footnoted. She offers just one asterisk of caution to her seaweed campaign.
“When you lift the hood on any of these solutions and realise the depth of the issue, you realise how interlinked everything is, how great the challenges are, and how no solution is perfect. There is no silver bullet for the climate crisis. There will be an ecosystem of solutions that solve the plastic problem, and we want that. We want diversity in our solutions.”
For now, Sway is throwing three species of seaweed at the wall to develop its packaging in partnership with the Beyond the Bag initiative. They’re currently running behind the scenes pilots with a whole host of fashion brands to address the 180 billion polybags that are used annually in the fashion industry (Fashion for Good), before launching publicly in 2023.
“We’re on a mission to find out what best tells the story of seaweed, what helps people to understand that it’s compostable and designed to be mixed in with your food scraps, and work out how showcase its natural aesthetic attributes — whether that’s a speckled texture or something like that,” Julia says, before sharing her most daring hopes for Sway’s future.
“I would love it if our primary model, say in ten years from now, was as an ocean restoration company. I’d love it if we just happened to use the seaweed, which we’ve resourced through regenerative farming, to replace plastics.”
If anyone can make the replacement of plastic packaging a side-hustle to a museum of regenerated oceans, it’s Julia Marsh. This woman makes cups out of internet-recipe seaweed in her apartment, tirelessly studies the science, partners with integrity and is as transparent about her hurdles as she is prolific with her solutions. She’s just the right level of obsessed with this slippery solution to make it stick.