How to Wildcraft Nori, Wakame and Other Seaweed




Photo by Marla Aufmuth

Strewn along beaches in tangled clumps, seaweed tell the fractal tales of tides. Holdfasts anchor them to rocks and their blades flow with the currents. In addition to being beautiful, seaweed is naturally high in many vitamins and anti-oxidants. Seaweed is rich in magnesium, calcium and iron. It's high in iodine, omega 3's and rich in vitamins. In fact, it’s one of the most nutritious things you can eat. These wonder algae have fertilized crops, saved populations from disease and hunger and are a very utilized wonder-food.

Research is also showing that the sex life of seaweed is rich and varied. Seaweed can be hermaphrodites, asexual, intergenerational, polyamorous, self-perpetuating, male-female traditional, and in winter-spring couples. Read more about this in the article "Lolita of the Seaweed." It stands to reason that with such raucous sex lives, seaweed is a potent aphrodisiac. This is in part due to the high vitamin B which gives you energy and helps with hormone production. It's rich in iodine, which is libido boosting, good source of manganese, a mineral known to help maintain a healthy sex drive.

It's even more libido boosting if you go forage it yourself. Imagine early morning at the beach, the excitement of the hunt, and escaping the impact zones just as waves crash. In Northern California, where I'm located, summer is prime foraging time, as seaweed has large blades during this time to absorb sunlight, and in the winter, they stay small to survive the storms.

You only want to harvest on low tide when the seaweed has been freshly exposed. If it’s on the beach, insects are already decomposing it. You can grab handful while out swimming or kayaking. While foraging, it’s a good rule of thumb to not take more than you need, but you can easily air dry seaweed and store it for later use. Virtually all seaweed is edible, though some is more delicious than others. The only toxic salt water seaweed I’m aware of is lyngbya majuscula found in Moreton Bay, Australia.

Step 1: Best Practices for Harvesting Seaweed

1. Stay away from areas that are heavily populated or have industrial or intensive agriculture runoff nearby.

2. Collect seaweed when the tide is low. Once it’s dry on the beach, insects may be breaking it down, so collect in the water, just below the tide line. Avoid any that look like something has been chewing on them.

3. Don’t yank seaweed from the rock it’s anchored to. Take scissors and snip, or tear a few leaves from a plant. Never take more than 1/3 from each plant so it can grow back.

4. Be careful when walking around rocks. Waves can splash through and knock you over, you can slip, and you can step on fragile tide pool creatures and kill them. So step lightly and be careful!

5. You may need a fishing license or permit to harvest seaweed. Check your state laws.

6. You can use your seaweed right away. To do this, rinse it under fresh water to remove critters, sand, and excess salt. To keep a saltier flavor, rinse it in ocean water. Seaweed can also be dried-hang it from a clothing line outside, or drape it on a pasta rack in your house. After it’s dried all the way through-usually takes a day or so, store in a brown paper bag in a cool, dry place. You can also freeze fresh seaweeds and take them out later. though the consistency can get make it not ideal for some dishes, so these you might want to use for soup stocks or making salt.

Step 2: Nori/Lavar (Porphyra)

Photos by Marla Aufmuth

Known in Japan as Nori, we are used to it in uniform, thin green sheets. However, this Nori has been processed, like wood chips to a sheet of paper. In the wild, they more resemble lettuce leafs. This plant is also called “lavar” in the British Isles and considered a staple there in seaside towns. The leaves of this plant range from red to dark brown to reddish purple. They are so thin-just one cell thick-they are almost translucent and have a pleasant, delicate mouth-feel.

Season: It’s best to harvest in springtime, as the fronds can start to harden by summer.

Best Uses: Since Nori is so thin, it's great for making seaweed salads. Lavar was commonly ground down into a type of “flour” for breads in Wales. Also good as flecks in crackers or sprinkled over loaves of bread before baking, and mixed with butter and even blended with citrus and made into salad dressings.

Step 3: Wakame/ Undaria Pinnatifida

Photo by Marla Aufmuth

Wakame (Undaria pinnatifida) a kelp originally from the Japan Sea. In Japan, it was once so valued and rare, it was used as currency. But then, as a stowaway it traveled overseas, attached to ship hulls. It arrived to the West Coast of the United States, Mexico, Italy, New Zealand through ports; it thrives in disturbed areas and quickly spreads through estuaries by releasing millions of microscopic spores. In the 1970’s, it grew popular in macrobiotic diets and at sushi restaurants.

Seasons: May through July are the best.

Best Uses: This kelp has long, flowing blades; to harvest, cut about 3/4 of a blade off and let the rest regrow. Wakame has a thick, sturdy texture and so is popular in seaweed salads and used in miso soup. Since it has such a firm texture and neutral flavor, I also use it to make kimchi and chips and crackers.

Step 4: Bladderwrack/ Fucus Vesiculosus

Photo by Marla Aufmuth

This pretty seaweed suffers from a branding/naming problem. Bladderwrack can be harvested year round. It grows on the sides of rocks, so snip off the tips, leaving the base clinging to the rock. It’s best known as a heavy duty source of iodine, and has been used to treat Goitre, an enlarged thyroid gland, caused by iodine deficiency.

Iodine is really important for brain development. A study reported in the Daily Mail has argued that if a woman has an iodine deficiency while pregnant there is a risk for her child's academic future, specifically in the areas of literacy and spelling. As quoted in Daily Mail's article, "[Researchers] suggest iodine deficiency may take more of a toll on the development of auditory pathways and consequently, auditory working memory." Their studies show that women who ate seaweed while pregnant have children with higher literacy scores.

Bladderwrack can be pretty intense iodine-wise and flavor-wise. Also, if eaten in large amounts, it’s a natural laxative. So use this one sparingly. Grind it down and mix with salt, add small amounts to seaweed salads, kimchi and use it to thicken soups. It’s also sometimes used to smoke meat and fish.

Step 5: Cystoseira Nodicaulis

Photos by Marla Aufmuth

Cystoseira is a lesser-known seaweed, but it's got a thick, crunchy texture and mild flavor. Pictured here, we put some on our bagels while out foraging. It's also great for making into pickles.

It floats about mid-tide zone, and so is easy to get to. Take it home, rinse well, and cut into bite-size pieces. One of my favorite ways to preserve it is to pour Ponzu sauce, which is a blend of soy sauce and yuzu.

Step 6: Dry, Store & Use

Once dried, your seaweed should last at least a year. I've included a link to harvesting kombu and some links to some seaweed recipe ideas and more are coming soon.

How to Harvest Kombu

How To Make Seaweed Salt

Homemade SPAM with Kombu Masubi

Homemade Salmon SPAM with Kombu Masubi

Dashi Broth Made with a French Press

Seaweed Kimchi

Seaweed Pasta



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    8 Discussions


    4 years ago

    Your awesome! Thank you! :D


    This is a very informative instructable! I'm now curious as to what seaweed is local to me on the east coast. One thing I'd like to point out though, you did refer to seaweed as a plant. While similar to plants in many ways, technically seaweed is an algae, not a plant.

    1 reply

    Thanks for the correction-I just tend to think of it as a plant due to the leaves. I think most of these are available to you on the East Coast-definitely kombu and nori, wakame and bladderwrack. I don't know about the Cystoseira, but you do have samphire or sea beans that are great pickled.


    4 years ago

    What an informative instructable. I never thought of all the different sexes nature offered. How interesting that seaweed reproduce in such passionate ways. I love sushi!

    the binks

    4 years ago on Introduction

    Great instructable, the nice thing is we find nearly all of these (or very similar) species over her in the UK too.

    Thanks for the ideas

    2 replies
    Maria Finnthe binks

    Reply 4 years ago on Introduction

    Yes, most of these are found all over the world. I just wasn't sure what the seasons were, but I bet the UK has similar seaweed seasons to California.

    the binksMaria Finn

    Reply 4 years ago on Introduction

    Yeah I'd imagine so.
    Though traditional Welsh Larvar bread has nothing to do with bread or flour, Its a mix of boiled Larvar & oatmeal usually fried in bacon fat. Quite nice a strange sort of way


    4 years ago on Introduction

    I love all of your instructables

    Thank you for providing such profound knowledge and unique ideas. I really appreciate it!