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Anyone ever put seaweed in their bins? I've heard it does wonders when put directly in the garden, but what about in the compost? I live two miles from the bay beach and recall there being some seaweed there.

Cool Member
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Joined: Tue Feb 02, 2010 1:03 pm

Yes I have used it and Seaweed is an excellent compost activator, so adding it to your compost heap will add nutrients and more organic matter to your compost. That's great

Greener Thumb
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I have added some to worm bins from the beach. I soaked it a few times in fresh water.

don't put too much.

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Fantastic idea! I live about 20 minutes from the beach and always see huge piles of the stuff out there. Might just be the reason we needed to head out one early morning with hot coco and bring home a few buckets for the compost pile!

Green Thumb
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So how much is too much because of the salt?

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Super Green Thumb
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I'm a 1000 miles from the nearest beach, so it's not really my issue. But if I did have access to seaweed, I'd want to rinse it off before throwing it in the pile, to get some of the excess salt off the outside.

In general we suggest no more than 10% of your pile be any one ingredient. I would definitely think that applies here.

Super Green Thumb
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In November 2009, there was this short thread on using seaweed in compost:

Cynthia H.
Sunset Zone 17, USDA Zone 9

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Hmm.. What do you guys think about fresh water sea weeds? We have a lake cabin about a half an hour from our home, and every year we get lots of weeds washing up on the shore, and some get raked out near the dock. Would these be just as good as stuff from the ocean?

Also, I don't have a compost pile yet, would it work to just mix some of the weeds into the garden soil? I had been mixing in grass clippings last year, those seem to be gone now.

The Helpful Gardener
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Sea salt can be very beneficial to soils because of the high trace elements; you even see it as amendment sometimes. I wouldn't worry about it too much... just did a nutrient density workshop where we discussed actually [url=]adding seas salt[/url] so the little bit that comes along fro the ride will be fine (as long as you have good biology and CEC).

Nope, freshwater isn't as good as ocean (less minerals in it's growing medium, so less goodies in it), but it's still good. I'd compost it as a really green item, but it should do a dream in compost with some good browns like leaves or paper...


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Super Green Thumb
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There's a pond at the bottom of my hillside that gets covered in duckweed. When I can get it together, I skim a bucket or two of that for the compost. It is a terrific green, very rich and of course very fine textured and moist.

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