Atlantic Mariculture

Kelp to crop

Atlantic Mariculture sells its kelp harvest as a biostimulant under the brand Tangled Greens: a cold-pressed liquid extract, Soil Association approved for organic growers, that changes how a plant uses nutrients and helps it resist drought and other stress. Most biostimulant seaweed today is still wild-harvested, and Innovation Manager Adrian Macleod points out the risk in that: warming seas, including in Nova Scotia where much of the industry's raw material comes from, could shrink those wild populations. Farming seaweed on ropes, rather than gathering it from the wild, is Atlantic Mariculture's answer. Trials run with the James Hutton Institute have shown yield gains of up to 30% under reduced-fertiliser regimes. National Lottery Climate Action Fund support pays for cameras under the farm and at control sites nearby, giving PEBL's monitoring the statistical power to show, across several farms at once, what a seaweed farm actually does to the seabed beneath it.

Watch the farm

Atlantic Mariculture

In Dr Adrian Macleod's words

From a PEBL interview, March 2026

• “There's a real risk that if we rely on harvesting from the sea, being hunter-gatherers of the sea and not farmers of the sea, we will run out of the seaweed biomass we need. One of the areas we get a lot of biomass from is Nova Scotia, and that's one of the fastest-warming areas.”
• “In Loch Sunart it's an incredibly biodiverse location. The last time I was at the farm we had whales, we've had dolphins come through, and we routinely see a lot of feeding activity with marine birds.”

How it started

Founded as GreenSea Solutions by Amabel and Douglas Hamilton, and based at Ardtoe Marine Laboratory on Scotland's west coast. Its East Oronsay site in Loch Sunart is often described as the UK's most productive seaweed farm, and the company has since helped install a similar rig system at Algapelago's Devon farm.

Who's behind it

• Dr Adrian Macleod · Innovation Manager