Seaweed Fertiliser - 1L

We have added a blend of pre-selected beneficial microbes to our fermentation process (using the Japanese Bokashi method) to make our biostimulant work even harder

Why seaweed biostimulant?

Our concentrated seaweed biostimulant helps you grow healthier, more resilient plants while building better soil — with less reliance on conventional fertiliser.

• Encourages stronger plant growth and improves soil condition
• Reduces the need for added fertiliser
• Ideal for veg patches, borders, lawns and outdoor pots

Use it on its own or alongside your usual feed. It's especially suited to organic growing, where artificial fertilisers aren't an option, and to poor or degraded soils that need rebuilding.

What it does

Seaweed's natural compounds help plants help themselves. Our biostimulant supports plants' own defence responses and improves tolerance to environmental stresses such as drought, salinity and cold. Thanks to seaweed's specific active components, it also influences the plant's natural growth-regulating hormones, and it feeds the soil microbiome — laying the groundwork for sustainable, long-term growth.

How to use

• Dilute 50 ml per 10 L of water
• Apply weekly — more often on poor soils
• Can be applied year-round, indoors or out
• Compatible with other feeds, fertilisers and treatments
• Monitor how your plants respond and adjust as needed
• 24-month shelf life

Need larger or commercial quantities? Get in touch.

Made exclusively from Cornish kelp, sustainably grown on our own seafarm and fermented with beneficial micro-organisms to unlock its full nutritional value.

How our biostimulant is different

The seaweed

We use mainly sugar kelp , the most widely farmed seaweed in the UK. Kelp is roughly 30% sugars — mainly alginate, mannitol, laminarin and fucoidan — and is especially rich in alginate and laminarin.

These sugars are what make kelp such an effective biostimulant:

• Laminarin has been linked to antifungal activity against mildew and grey mould (grapevine study), improved tolerance to heat and salt stress (Brassica study), and activation of plant immune signalling (the PAMP- and MAMP-triggered responses that switch on a plant's defences).
• Alginate has been shown to support water-stress tolerance by stimulating the abscisic acid signalling pathway (cucumber study). Its gel-like properties also help bind soil and metal particles together.
• Mannitol and fucoidan trigger similar plant defence responses.

Most seaweed biostimulants are made from egg wrack (Ascophyllum nodosum), the most abundant species in the sheltered rocky bays of Scotland and Ireland. Its widespread use probably has more to do with availability than with being the best seaweed for the job.

The environment

Egg wrack is wild-harvested. There's nothing inherently wrong with that, but it comes with trade-offs. Wild harvesting always takes something from the natural environment, however carefully it's done. And because a seaweed's sugar and mineral content shifts through its growth cycle, harvesting from the wild all year round means every batch is different.

We grow and harvest our kelp on our Cornish farms in Fowey and off the Lizard Peninsula. This lets us harvest at peak sugar content and deliver a consistent mineral profile batch after batch — something growers and horticulturalists can genuinely rely on.

The recipe

There are several ways to get liquid out of seaweed. The most common is cold pressing, which extracts the liquid but leaves much of the nutrition locked away in the solids — so a lot of the goodness goes to waste. Instead, we ferment our kelp using the tested Japanese Bokashi method, adding beneficial microbes and molasses. This breaks the whole seaweed down into a living, active product that delivers the full range of nutrients and benefits to your plants and soil.