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Kelp farming lessons to kickstart an industry

Updated: Apr 9

Bountiful harvest: farmed sugar kelp. Photo: GreenWave

Kelp farmer Bren Smith, co-founder of the US ocean farming organisation GreenWave, offers some lessons for Australia in developing a seaweed farming sector here.

When the US-based non-profit organisation GreenWave launched its first online course, ‘How to start a kelp farm’, in January 2023 there were more than 1300 people from 40 countries, including Australia, registered to take part.

The demand demonstrates the “tsunami of interest” in seaweed farming, says GreenWave’s director of training and support, Lindsay Olsen, who leads the program.

GreenWave’s aim is to promote not only the amazing potential of seaweed, but also the challenging realities of entering an industry that is still just beginning to establish its identity and markets in the US after more than 20 years.

By comparison, seaweed farming in Australia is less than a decade old, and much of that has been in the research phase rather than in commercial production. (In countries such as Japan and South Korea, seaweed has been farmed for more than 400 years.)

Support for industry development

GreenWave focuses specifically on kelp as part of a regenerative ocean farming system, offering training and information to help businesses get started. It wants to ensure that those who take on ocean farming are well-prepared, rather than watching a string of unsuccessful ventures undermine confidence in the future of the sector as a whole.

GreenWave’s Ocean Farming Hub provides the central point for resources, including courses, more than 80 ‘How to’ videos, an ocean farm design tool, budgets, gear lists and a community forum. The community discussion forum is for both new and established ocean farmers and has attracted more than 4000 members since launching in April 2022.

In the face of exponential interest in seaweed farming, GreenWave co-founder Bren Smith says the latest course – ‘How to start a kelp farm’ – is an attempt to reach more people with the information they need about whether ocean farming is for them. It provides an important reality check for would-be farmers in the US and elsewhere.

He also spoke to about lessons from the industry’s development in the US that countries such as Australia could make use of. While Australia’s First Nations people have used seaweeds in many ways for millennia, the commercial farming of seaweeds is an emerging sector for the country.

Bren’s lessons from the US include :

● Permits and licensing – bureaucratic barriers

● Scaling-up – farming not gardening

● Food, climate and community support

● The supply chain – moving all parts together

● The right capital and the Kelp Climate Fund

● Turning passion into action

Top left: Outplanting seeded lines. Top right: Bren Smith harvesting sugar kelp. Bottom left: kelp and shellfish farmed together offer a diversified, restorative ocean farming system. Bottom right: Beginning harvest. Photos GreenWave


Permits and licensing – bureaucratic barriers

Bren highlights the marine lease and permitting process as a critical starting point that shapes the industry.

“The more burdensome and expensive permitting is, the more it creates a barrier to entry, where you have to be a large corporation in order to get a permit,” he says.

This potentially leads to an industry dominated by a few large players, rather than a more-inclusive one with a greater diversity of players.

“It’s really important that you keep an eye on who farms. It matters. [Minimising] the cost of the bureaucracy, of the permitting, is a huge way to ensure that you’re getting horizontal rather than vertical growth rate of an industry – many smaller participants, rather than just a few large ones.

Apart from keeping the cost of the process to a minimum, he says having a central clearing house to handle applications and having environmental assessments handled both help to streamline processes.

“I think of permitting as an opportunity for government officials to create a short and efficient roadway for regular people to take part. The promoters, civil servants, politicians – they often really want to see this happen. So, we really have to make sure they don’t get in trouble for saying yes. You really need to de-risk it for them, in part.”

From an industry perspective, he says, that can mean putting in quality applications, with standardised farm designs that have been tried and tested for issues such as mammal entanglements.

Scaling-up – farming not gardening

While Bren supports an industry that has space for many players, he’s not a ‘small is beautiful’ advocate, nor ‘big is better’.

Rather, GreenWave supports a distributed network approach to scale, to diversify production risks for producers and for markets.

But growing seaweed does need to be about farming, not gardening, he explains. The scale of the climate crisis is such that substantial quantities of seaweed will be needed, he says.

“The ocean – it’s a hard place to grow food. It’s high-risk. So my view is that to have climate impact and scale fast and to get a huge amount of seaweed in and out of the water, we need to have 10,000 farmers, not five."

“You also want all those folks learning from each other. You want that workforce. And to scale quickly, you need social licence.”

Food, climate and community support

If seaweed is to be a climate solution, it has to be both about driving down carbon and lifting up communities, Bren says.

“You can’t just address the carbon–climate question and then leave everybody behind in the process because you’ll never get climate legislation. The politics won’t work. You need to keep those two tied.

“We need an incredible amount of regenerative crops – seaweed and shellfish – in the water as our land-based food systems are being pushed out to sea.

“Our wild fisheries cannot handle that large burden. So we’re going to be farming the ocean. We really believe regenerative species such as kelp and shellfish are the way to go.”

“The more hands (there are) on deck, the more you’re going to get community, governments and societal buy-in to set up farms in a public common, which is the ocean.”

The supply chain – move all parts together

In the US, the industry has developed somewhat organically, Bren explains. A few people began farming, and then a hatchery followed. There was some university involvement, and then a processing facility. But it was an uncoordinated and somewhat chaotic development.

“Hatcheries would find themselves with seed they couldn’t get rid of, and a farmer would have too much kelp they couldn’t find cold storage for. An entrepreneur would do really well with a kelp burger, but then find there was not enough supply,” he says.

“If you don’t have cold storage, if you don’t have a hatchery, if permits are getting held up – all these sorts of things – then everybody fails.

"There needs to be a large table early on with all the folks in the supply chain, the right kind of investment in these different pieces of the supply chain that move it all at once in an organised way so that everybody succeeds.”

One step GreenWave advocates to help smooth this process is the use of forward contracts for kelp crops. “We don’t think anyone should farm without a forward contract,” says Bren.

An integral part of the supply chain is the land-based infrastructure and processing requirements.

“Farming is quite affordable in the water because it’s just ropes and buoys and anchors. But once you hit land everything gets really expensive,” says Bren.

GreenWave has already established hatcheries and is supporting farmer-owned infrastructure for dockside processing to stabilise harvested kelp, allowing farmers to get higher prices for their crop.

But further processing to meet market requirements remains complicated, Bren says.

“There is a lot of market pull. There’s a huge number of people who want to buy seaweed but they all want it in different forms. There is no consensus on what commodity they want – 100 per cent pelletised, powdered, a kelp slurry . . .”

In some areas, GreenWave has helped to bring kelp farmers and private companies together to normalise product specifications and volumes to help address this issue.

Sugar kelp ready to eat. Photo GreenWave


The right capital and the Kelp Climate Fund

“Another challenge for the industry is, quite honestly, that very often it’s the wrong kind of money being invested,” adds Bren.

He says equity and venture capital firms want to make large investments. In the past, these sources of finance have not been a good fit for food and agriculture which is very capital-intensive. But it’s a good fit for value-added companies such as biomaterials.

“Supportive finance options for farming may look more like forgivable loans and subsidies,” he says.

GreenWave’s Kelp Climate Fund is part of that supportive financing approach. The fund is in its second year and provides a subsidy of up to $25,000 to ocean farmers to support the positive climate impacts their kelp crops provide. This includes the removal of carbon and nitrogen from the water and contribution to reef restoration.

In return, farmers provide key monitoring data on outplanting, growth rates and harvest via GreenWave’s My Kelp app. GreenWave aggregates this data to track acres planted, carbon and nitrogen removed, and harvest volumes throughout North America. Bren points out this is not about carbon sequestration and trading carbon or nitrogen credits.

The science, the policy and the markets on these ‘blue carbon’ markets are still very much a work in progress, he says. He sees the Kelp Climate Fund as a short-term measure, filling the gap until robust trading markets are established.

“What we’re really trying to do is get more kelp in the water,” he says.

From left: Getting kelp in the water – seeded line, ready to outplant, and the final harvest. Photos: GreenWave


In the 2021–22 farming season, the Kelp Climate Fund pilot included nine farms around the country and paid farmers more than US$75,000. For the 2022-23 farming season the fund has increased to $335,000, to support more farmers, funded by a number of philanthropists. Bren says GreenWave’s goal is to grow the pool for kelp climate subsidies to US$1 million by 2025.

Turning passion into action

An ongoing challenge is turning the huge community of passion for seaweed into a community of practice – a challenge that GreenWave was specifically founded to address.

It’s one Bren remains increasingly optimistic about. The thousands of people who have registered to receive training from GreenWave, both in person and online, over the past few years is a testament to the growing global enthusiasm for kelp. So too is the explosion of interest in the chemical components and alternative uses for kelp and other seaweeds.

As a grower and advocate for more than 20 years, Bren suggests that the powers of kelp have really begun to emerge, creating what he hopes will become the tipping point for the industry in the US, and elsewhere.

“It’s less the kelp but what’s in the kelp – all these things that the world needs, such as carbohydrates and proteins. These things are increasingly expensive on land because of the costs of freshwater, fertilisers, access to land,” he says.

“What we’ve begun to see, whether it’s ingredients companies, biomaterials companies, or bio-stimulant companies – they’re all looking at what’s in the kelp."

“There’s huge potential. But the unit economics have not been worked out yet. It costs a lot to extract those compounds. So there’s a big race around the country and world to process that kelp in an affordable way to get those compounds.”

In the meantime, for Bren and for GreenWave, it’s about training more people and developing successful farms and markets that turn a passion for seaweed into action that supports seaweed farming, in the water, and out.

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