From Shore to Shovel

Repurposing crab shell to
nurture plant health and growth

Who are
Sea the change?

We are a small business who sea-cycles. We gather a natural waste product from the seas around Guernsey and repurpose it for good.

One man's dream

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Our Product

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Our crab shell fertiliser is pure and simply crab shell. Washed in sea water. Dried in the Guernsey sun. Nothing added. Nothing taken away.

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Easy to apply, with vigorous growth and excellent productivity across all my fruit and veg.
Lucy Allotment grower, Guernsey.

Why crab shell fertiliser is so fiendishly clever

Microorganisms in the soil get very excited because the crab shell has lots of yummy nutrients to eat. They gather round and produce an enzyme called 'chitinase' – a bit like a human saliva - which breaks down the crab shell and releases chitin from the crab shell into the soil. The more they eat, the more they breed so there are soon lots of microorganisms producing lots of chitinase. The clever bit is that the chitinase also breaks down the chitin found in the exoskeletons and eggs of harmful nematodes such as the Root Knot Nematode and gets rid of them. Root Knot Nematodes cause 5% of global crop loss, attacking the roots of crops like tomato, cucumber, strawberries, onions and lettuce to name a few.

So now the soil has lots of chitin in it. The walls of many nasty fungi, (infecting pathogens) also have chitin in. Plant cells contain immune receptors. When they detect the chitin they think they are under attack by aggressive fungi. Natural defence mechanisms are triggered and an immunity to the pathogens occurs, protecting the plant against future attack. Blight and wilt diseases such as Fusarium Wilt, often associated with tomato plants, are caused by pathogens.

Meanwhile, as the crab shell breaks down, it provides a slow release of calcium into the soil. The plant absorbs the calcium as it needs it, and uses it to strengthen its cell walls, promote cell division and growth. Strong cells are good for disease prevention too, tackling annoying things like Blossom End Rot on tomatoes.

That's it. Don't you just love nature?

Buy Guernsey Crab Shell Fertiliser direct from
one of our lovely stockists in Guernsey and the UK