One of the exhibitors at Ocean Talks 2025 is Yorkshire-based seaweed farm SeaGrown, pioneers in an innovative method of cultivating seaweed. From capturing carbon to restoring ocean biodiversity, seaweed is emerging as a powerful natural ally in the fight against climate change as well as being used to create biofuels, textiles and fertilisers, amongst others. Ahead of the event, founders Captain Wave Crookes and Laura Robinson tell BOAT about their story.
How did the two of you first come up with the idea for SeaGrown?
We met aboard the RRS James Clark Ross during a British Antarctic Survey research expedition, where Wave was the ship’s Navigating Officer and Laura was onboard as a scientist exploring deep sea ecosystems and climate. Sharing a deep passion for the ocean and concern for its health, conversations started about tangible, deliverable solutions which wouldn’t end up being ‘all talk and no action’. We also wanted to be able to spend a bit more time at home! We realised that by combining Wave's practical experience both on and under the sea with Laura's marine science knowledge, we could create something unique – a way to actively restore ocean ecosystems using the power of seaweed, leading directly to the inception of SeaGrown.
You grow the seaweed offshore instead of sticking to foraging or coastal cultivation. Why?
Foraging is inherently limited in scale if done commercially. Coastal cultivation exists as a niche industry, but suitable sheltered sites are scarce and often conflict with other marine users. To make a truly significant positive impact on ocean health – sequestering large amounts of carbon, meaningfully improving water quality, creating substantial habitats for new biodiversity – requires scale. That meant either going offshore into more challenging, but more available, waters like the North Sea off our Yorkshire coast – or designing a system that could co-exist with other marine users and reduce conflict in coastal waters. This necessity drove the innovation of our Kelpedo™ system.
What kind of seaweed do you grow?
We focus on cultivating native UK kelp species, primarily Sugar Kelp (Saccharina latissima), Oarweed (Laminaria digitata), and Alaria (Alaria esculenta), as these are perfectly adapted to North Sea conditions and are already found in abundance on the nearby coast.
We cultivate the seaweed using our innovative Kelpedo™ system. Each Kelpedo™ unit is individually anchored and features vertical structures seeded with microscopic early-stage kelp from our onshore hatchery. These units are deployed where needed, allowing the kelp to grow naturally, suspended at the optimal depth in the water column.
Tell us more about your Kelpedo™ system...
It is the only flexible, scalable solution for growing seaweed and shellfish in open, offshore waters. It can also be used inshore or even in port without interrupting the activities of other marine users – either marine industries or leisure users.
Kelpedo™ is survivable in offshore conditions, and because of its modular design it can easily be co-located with other essential offshore industries such as offshore wind, cables and fishing. This means that these sectors can deploy Kelpedo™ units in any location, in areas of any shape or size, to minimise the impact their work has on the marine environment with no interruption or interference with their own operations.
We are also looking into securing minor Government policy changes so that Kelpedo™ could be operated by fishing vessels as a diversification activity, reducing pressure on fish and shellfish stocks whilst delivering environmental benefits to support them. Finally, Kelpedo™ is targetable, meaning the system can be accurately deployed to solve problems such as degraded water quality at source, then quickly removed, if required, once the job is done.
In short, SeaGrown is able to work with the marine industry, not in conflict with them, to improve the health of our oceans and generate social benefits for the coastal communities which rely on them.
Why is seaweed so important?
The UN Environment Programme has declared a ‘triple planetary crisis’ - climate change, biodiversity loss and pollution. Seaweed cultivation can help with all three of these problems, so we do agree that it has a key role to play in maintaining the health of our planet.
On carbon sequestration, kelp is very fast-growing and absorbs large amounts of CO2 directly from the seawater whilst releasing oxygen. If that carbon can be locked up in the seaweed, it can be sequestered.
SeaGrown is working on a number of ways of not only locking the carbon up, but leveraging the effect of the seaweed by using it as a substitute for other high-carbon ingredients in food and agricultural products. Whilst it’s doing this, our seaweed is also creating habitat for marine life and improving water quality into the bargain! We would never claim that seaweed is the 'silver bullet' to fix all of our environmental problems, but technologies like Kelpedo™ allows it to be used as a vital, agile weapon to fight climate change alongside a global strategy for reducing emissions.
You call seaweed a 'supercrop'. Tell us why...
Seaweed's potential is enormous! Beyond food, extracts can be used as highly effective agricultural biostimulants, improving crop yields and stress resistance while reducing the need for synthetic, high-carbon fertilisers.
The biomass itself can be also processed into biofuels, textiles or used as feedstock for bioplastics, offering sustainable alternatives to things we all use every day. Furthermore, compounds like alginates and fucoidans have countless industrial uses, replacing synthetic chemicals. Seaweed is a true supercrop and has the potential to become a cornerstone resource for a more sustainable economy.
Do you hire out your innovation to other companies?
SeaGrown works with other companies through two main routes. We offer turnkey solutions where SeaGrown operates, maintains and monitors our Kelpedo™ technology for our clients at their sites, to support them with minimising the environmental impact of their work.
We also have our "Plant a Tree in the Sea" initiative, where companies can partner with SeaGrown to grow Kelpedo™ units in the water at our site to achieve measurable environmental outcomes and meet their sustainability goals. This is especially relevant for marine businesses, or individuals whose activities have an impact on the marine environment, but it can equally apply to any other business looking to improve the health of our oceans through partnership and proven solutions.
Talk us through a day in the life at SeaGrown…
A day is incredibly varied! It could involve the SeaGrown crew heading out on Bright Blue at dawn to deploy new Kelpedo™ units or examine existing ones for maintenance, or biodiversity assessments. Our scientists might be analysing biodiversity or water quality data or working in the hatchery nurturing the next generation of kelp. Some of our staff are also making or carrying out product development for our food seasonings or bath range, logistical planning for operations, or holding meetings with potential partners for our "Plant a Tree in the Sea" initiative. Every day blends hands-on marine work, scientific research, and developing sustainable business opportunities.
Wave, you have roots in Scarborough's fishing industry - do you think seaweed cultivation could help replace some of the lost fishing jobs?
You’re absolutely right, although I’ve done many exciting jobs both on and under the sea, my roots are firmly in the fishing industry and I understand the challenges our fishers are facing. We are not suggesting seaweed cultivation could, or should, ever be a direct replacement for traditional fishing, but it certainly could offer a genuine, practical diversification opportunity with wide scale benefits.
Our Kelpedo™ system was designed specifically to be workable by small vessels using the standard deck machinery fitted to many fishing boats, minimising adaptation costs. If the Government will approve some minor policy changes, SeaGrown could provide a way for fishers to use their existing skills and vessels in a new, sustainable marine industry which will work in harmony with traditional fishing: securing jobs and creating additional income for our coastal communities whilst improving the environment for the fish stocks they rely on.
Laura, as a climate scientist, what drew you to this hands-on marine project?
While academic research is vital, I was increasingly drawn to translating science into tangible action. SeaGrown offered a unique opportunity to apply decades of research on marine ecosystems and climate change directly, to developing real-world, nature-based solutions. It’s incredibly rewarding to see scientific understanding lead to practical methods for restoring ocean health, sequestering carbon, and boosting biodiversity – making a measurable difference that goes beyond publications. It's about putting the science to work where it's needed most. It’s also been really valuable for my students and mentees to learn about how academic research can be used for impact – both in the sea, and across local communities.
What’s your vision for SeaGrown and how could it scale across the UK - or even globally?
Our vision is for sustainable seaweed cultivation to become a cornerstone of ocean restoration and the blue economy, both in the UK and globally. We are currently working hard to demonstrate our Kelpedo™ system across the full range of real-world, operational use cases in the north east of England. This is allowing us to create a validated, repeatable model which could be adopted anywhere. SeaGrown is all about achieving the maximum possible positive impact for our marine environment, so we would be very interested to talk to any UK marine business interested in working with us for healthier oceans. We certainly do intend to offer our system internationally and we are currently seeking suitable partners, so if that could be you, please get in touch!
Now in its eighth year, Ocean Talks will return to London on 12 June 2025, celebrating ocean conservation efforts in the week running up to World Oceans Day. Tickets are free but guests must register their attendance.
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