Three kinds of progress in seaweed, and why the difference matters

Three announcements in the first week of October were each described as progress for seaweed. A farm in Alaska grew giant kelp. An Australian company signed a distribution agreement with a target of 480,000 cattle. A study in Massachusetts reported what several years of kelp farming there have taught.

Each of these is progress. They are not the same kind of progress. I find it useful to separate three questions: can it be made to work, can it reach a customer, and can it earn more than it costs? This note takes one example for each.

1. Technical progress: can it be made to work?

WildBlue Mariculture ran a trial of giant kelp at its farm in Simpson Bay, Alaska, in the 2025 to 2026 season. The farm put out about 2,000 feet of seeded line across four sets of lines. The kelp took hold on all four. One set, with 600 feet of line, was harvested on May 14 and gave 1,163 pounds of wet kelp. The farm's report puts this at about 1.94 pounds per foot of line.

That is technical progress. The report states that WildBlue was the first kelp farm in Alaska to plant giant kelp, and the trial shows that the species can be established at the site.

The report is equally clear about what is not yet shown. WildBlue considered the yield below the level it wanted. Only one set of lines was harvested. By July the remaining kelp had deteriorated and monitoring ended. The report states that the trial leaves commercial yield, spacing and harvest timing unresolved.

A comparison gives a sense of the distance still to go. The Massachusetts report described below cites a Maine study that put the yield a sugar kelp farm needs to cover its costs at 2.69 pounds per foot or more. GreenWave reports that the farms it found to be profitable averaged 3.5 pounds per foot. These figures are for other kelps and other places, so they are not a test of the Alaska trial. They do show the kind of number a trial has to be set against: yield per foot, the price a buyer pays, and the cost of growing and harvesting each foot.

2. Market access: can it reach a customer?

On October 7, Sea Forest announced a distribution agreement with Teys Australia, one of Australia's large beef processors. Sea Forest sells SeaFeed, a cattle feed supplement meant to cut the methane that cattle release. Under the agreement, Teys is the exclusive distributor of SeaFeed to the beef industry in Australia and New Zealand until August 2030. It must meet purchase targets to keep that exclusive position.

This is market access. A company with customers, feedlots and distribution has agreed to carry the product.

The announcement also shows what is still open. The 480,000 cattle is a target for June 30, 2027 that the two companies agree to work toward. It is not a purchase order. It includes about 70,000 cattle in Teys's own feedlots, where the product is already in use. The price will be agreed between the two companies as they go.

One more point matters for seaweed growers. Sea Forest describes SeaFeed as a "nature-identical" formulation of the active compounds found in Asparagopsis, a red seaweed. The announcement does not say how much farmed seaweed the product uses. More cattle on SeaFeed may or may not mean more demand for seaweed, and I could not confirm it either way from this document.

3. Business viability: can it earn more than it costs?

A report released in Massachusetts on October 6 shows what happens when the first question is partly answered and the third is not. Cape Cod Cooperative Extension and its partners ran test plantings at 15 sites south of Cape Cod. Only one, Falmouth Harbor, showed modest success. At most of the others, the water held too little of the nitrogen that kelp needs in winter, or was not salty enough.

The team also interviewed 10 people who have grown kelp in the state. Most had farmed it for two to four seasons and then stopped, because the kelp did not grow well enough or did not pay. One was still farming kelp at the time of the study.

Several of them said that growing the kelp was not the main difficulty. Finding a reliable buyer was. The report also notes that the state has little shared capacity for drying, storing and processing kelp, so each grower had to do that work alone.

The lesson is that a site where kelp grows is one part of a business. A buyer is another. So is a way to dry or process the harvest. The price also has to cover all of it.

How to use the three questions

When a seaweed announcement arrives, the three questions can be asked in order.

• Technical progress. What was shown, at what size and at what site? What does the team say is still unresolved?
• Market access. Who is the customer? Is there a firm order, or a target? Has a price been agreed?
• Business viability. What does it cost to produce and deliver? What does the buyer pay? Are the sales repeated?

A venture may be strong on one question and still working on the others. That is normal in a young sector, and it does not take away from what has been achieved. The difficulty comes when all three are reported as the same thing, because operators and funders then lose sight of what remains to be shown.

In my view the three stages also call for different money. Grants suit technical trials and shared facilities. Lending becomes realistic once a business can show repeated sales at a price above its costs.

Discussion question

What evidence would you want to see before calling a seaweed venture commercially viable?