If I tell you that all the seaweed you see on your local beach is edible bar one* which is not likely to be present anyway – does that demystify the whole subject a little? At Wild Harvest we teach many different subjects broken down to be easily accessible for beginners and yet which take our learners to a level of basic proficiency. Its ok to be a master of one subject like foraging, or an artist in something like basketry but where will that get you if the situation is not about pleasure but survival?

So, this Seaweed Survival blogpost is designed to give you enough knowledge to make some basic foods and still benefit from the same bountiful health benefits that eating fancifully prepared and nominally challenging recipes will bestow. I believe we should be unashamedly pragmatic in our learning journeys in order to keep moving forward, there is no need to make the learning journey so complicated, information overload stops us starting.  At Wild Harvest we encourage people towards the confidence to move from ‘head-to-practice’ by giving simple easy to follow instructions and just enough peripheral knowledge to interest not overwhelm you – so here are the seaweed survival basics to give you the confidence to get out:

There are some general harvesting and processing rules that can learned for foraging in general and can apply to coastal foraging too without the need for much more, for example

Harvesting – from an unpolluted environment, at the optimum time of the day/year for the best nutritional benefits and safety of the collector, without uprooting – just cutting a plant and not stripping a resource bare when you find something you like.

Processing – once you know that most of our seaweed is edible the only difference is preference for one taste over another ie palatability rather than actual edibility. It is simply preference that will determine how you process seaweed because all of it can be processed in pretty much the same ways.  In a survival situation of course palatability or preference is less of an issue than edibilty and nutritional value – all of our seaweed can be quite tastily:

Patted dry and fried from fresh either shallow fry or deep fry into crisps
Boiled/added to mash potato or cooked grains and cooked in oil or fat as patties
Boiled as a vegetable

Eaten (a little) raw (if sea is clean)
Dried and crumbled or powdered and stored in a jar for later rehydration in a stock or soup.

Health benefits of eating seaweed

Seaweed is one of the few foods that is contains all of the 56 trace elements essential for human health, amongst them is calcium, iron, magnesium, iodine, potassium and selenium (the latter becoming scarcer in farmed land veg due to soil depletion). The brown sea weed especially is rich in alginates …… and fibre for the digestive tract. Seaweed is a low fat and calorie food despite being also high in fibre and minerals. Purple seaweed like Laver contains more B Vitamins while Kelp in particular is rich in Lignans which are pre-cursors in the body to the formation of phyto-oestrogens. This is linked to Japanese women’s low incidence of breast cancer. The Okinowans from an Island off Japan eat between 7 – 10 portions a day and are the worlds oldest nation. Iodine present in seaweed helps with thyroid functioning.

Seaweed is cited as ensuring a healthy heart and digestive system and can also detox the body of heavy metals. It is a useful ingredient where there has been a radiation leak.

Note the drying of leaves does not compromise the nutritional value as its mostly water that is lost though any vitamin c will deplete with oxidation and heat.

Mermaid Beauty

Topically seaweed is good for hair, scalp and skin (face and body) its unusually rich combination of minerals, nutrients and amino acids are drank up by the skin and absorbed by the hair to give a shiny healthy appearance. It moisturises, is beneficial for anti-ageing and calms senstive and spotty skin. Add dried powdered sea weed to soap making, bath salts, or body butter and conditioners.

Making iodine solution.

Steps to extract iodine from seaweed:

Burn some seaweed in a metal container above heat.
Wash the ash with distilled water, filter it through cloth or coffee filter paper.
Boil the water until there is just watery salt left.
Put this in a glass jar.
Now add sulphuric acid (car battery?) – the water should go purple brown. (When you add the sulphuric acid it hisses and some liquid evaporates there’s a possiblity that if you put muslin cloth or iodine paper over the jar you may catch some crystals).
Adding sodium hydroxide dissolves the iodine crystals into the solution and neutralises the acid.
You will have a brown liquid that you can test the strength of (how many ppm from 0 – 50 of iodine) using iodine paper (a bit like litmus paper).

Fertilize Your Soil With Seaweed

One cold November when back-packing alone with two toddlers I stayed at a community in Scotland.  Erraid is the smaller sister community to Findhorn and I earned our stay there by trudging up and down to the beach to collect seaweed then covering the growing beds with a deep layer of mulch.  Over winter the seaweed would rot down nourishing the soil ready for Spring and in addition to the usual benefits of any mulch seaweed has the extra advantages of:

Not carrying weed seeds

Not carrying diseases of land plants

Breaking down easily

Rich in Selenium


*Desmarestia – is the name of the toxic seaweed. It is a fine frond-like pale green-brown seaweed that grows in inter-tidal waters and emits sulfuric acid and has out of the water a ph of 2% so would burn your digestive system (perhaps you could use this in your iodine making experiments to get the iodine out of seaweed?).


“I grew up on the wide sandy beach at Marske-by-Sea on the North East Coast, barefoot and raggy-haired, alone, dreaming of joining the mermaids.  My school was only seventy metres from the beach so I even chose coastal erosion as my geography project to justify to the teacher why I should spend his lessons ‘on-site’.  Moving inland to live on farms in Yorkshire subsequently meant I’ve lost touch with the wide skies and the fresh salty smell of the coast  – if you are lucky enough to live near the coast make a pledge now with me to get out to the beach soon and bring seaweed into your life!  Post your pictures on Facebook and remember to tag ‘Wild Harvest School of Self-Reliance’ – we offer prizes every couple of months for the best tagged photos! – Di Hammill x