meshmouse
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Joined: Fri Jul 11, 2014 10:14 am
Location: Long Island NY USA zone7a

Can I add too much Seaweed?

I'm assuming all seaweed is a green (no matter it's actual color). I know it needs a good rinse for salt residue. I know it needs to be fluffed amongst the browns (with good aeration).

My question: Once it is dried on the shoreline, is it still a green or is it a brown (and, can I over do its application)?

Thanks - meshmouse

tommyblaze
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Location: Long Island new york

Depends on what seaweed we are talking about?

toxcrusadr
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Usually green materials will retain a lot of their nitrogen when dried. I know it works with grass clippings. I've never worked with seaweed so I don't know for sure.

meshmouse
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Joined: Fri Jul 11, 2014 10:14 am
Location: Long Island NY USA zone7a

Thanks for the response folks -

tommyblaze,

Does the type of seaweed matter? I don't know the particular names of the various seaweeds, but I see you are a fellow Long Islander, so I will say the normal stuff you find on the North Shore. I'm guessing there's at least 6 varieties I can think of. Brown, green, yellow, purple, etc.

Tox -

Yes, I seem to remember from reading about composting on this forum last season, that leaves that are harvested green are considered greens even when they are dried. I think it was like you say, that the nitrogen levels were still the same as when fresh. I'm going to assume that seaweed is still a green even when dried on the shore.

I know seaweed is very nutrient rich and I'm worried that too much might not be a good thing. I'm gonna guess there's no such thing as too much of a good thing (in balance with browns) and use all I can get. I'm thinking it would be more nutrient dense than grass clippings, but I don't know. I'm rich in leaves and seeking greens.

Thanks,

meshmouse

tommyblaze
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Location: Long Island new york

If its eel grass it takes forever to breakdown. I am going to use it as mulch.

imafan26
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Location: Hawaii, zone 12a 587 ft elev.

The salt in the seaweed is the main problem so it needs a good rinse. After it is dried and there is still a lot of salt crystals on it, it needs to be rinsed again.

You still need to balance greens and browns in your compost pile. Too much greens of any kind will get you a stinky slimy mess. Grass, seaweed, kitchen waste, manures, are all high nitrogen greens. I read that the easiest way to tell if something is a green or brown is the water content. If it has a lot of water like green leaves and kitchen waste it has more nitrogen and is a green. Old leaves that have fallen and leaf mold have lost most of their water and nitrogen so are mostly brown.

Browns are high in carbon. The stems and branches of plants, newspaper, cardboard, straw, old leaf mulch are browns.

For a balanced pile you want to end up with a C:N ratio of 25:1. This will give you the perfect balance for a hot pile.

All carbon is not equal . Newspaper has a C:N ratio of 170:1.

The rule of thumb is to chop up the browns and greens to help them decompose faster. A ratio of
2 parts brown to 1 part green works in most cases.

Composts piles require Greens for nitrogen, most of which the microbes will consume during decomposition and some of it will also volatize off. Carbon for food, water, air, a shovel full of soil to seed the pile with the microbes, and time.

meshmouse
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Joined: Fri Jul 11, 2014 10:14 am
Location: Long Island NY USA zone7a

tommyblaze -

Thanks for the heads up on eelgrass. I did a quick Google and it sent me to Cornell U page of seaweed in general and then eelgrass in particular. Very interesting history of uses (including as insulation in the first Frigidaire refrigerator). Now that I know what it looks like I will avoid it for compost.

imafan26 -

Thank you for the quick review. I had forgotten a few things (like not all browns being equal, for example). I do keep a pile of sticks and twigs off to the side of my pile and every year or so I scrape off the the top and add the humus to my compost, but it's not a lot.

And yes, I always add a little finished compost to my new piles/layers to seed the microbes.

When I gather seaweed, I take a 5 gal bucket, and anything alive (still attached to a rock or shell) I leave alone. I also harvest over a wide area, a little here, a little there. Apparently there are all kinds of bugs and such that rely on even dried seaweed to thrive. Don't want to mess with the ecosystem too much.

At home, I dump the bucket into a little kiddie pool, fill with water, stir a little, let sit for an hour or so, dump water and repeat until three rinses made. So far so good.

I try to keep the 2 to 1 ratio of browns to greens and so far, things seem to be working well. But let me ask, that would be by weight, not volume, obviously? So my dry fluffy leaves are greater in volume than my moist clippings/scraps, but by weight is how to balance 2:1 ratio?

All my kitchen scraps get pureed in a food processor (keeps the critters away), but I really don't have a way to break up the leaves other than to run them over with a lawn mower which is a lot of mess and effort. By the time I start adding leaves in the spring, they've already had a winter by themselves to break down a bit anyway. I haven't had slime problems and get pretty good heat (140F+) at peak of pile.

I live in a small house on a small plot and while it's all nicely appointed, it's like living on a ship. There's not a lot of spare space where one could store even one of the smaller chippers I have seen available (as much as I would like one). If I want to buy a frying pan, I've got to figure out which one I'm going to ditch before I do.

So, even tho the seaweed is dried, it's still a green. Is that right? It's freshly, recently dried, not last years crop washed up.

Sorry for rambling and thanks for the review.

meshmouse

imafan26
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Location: Hawaii, zone 12a 587 ft elev.

If you do it by weight the greens with more water will outweigh the browns every time. I was told that if everything is chopped, run over with a mower, put trough a shredder or chipper or chopped with a machete into bits that is better than chunks. The measurement is volume not weight so one bucket of chopped up greens to two buckets of chopped up browns.

What you want to strive for is variety so all your greens are not seaweed and all your browns are not cornstalks. It would be ideal to have carbons that already have the 25:1 ratio, but that doesn't always happen, but if you get a nice blend of different browns hopefully, they will help balance each other out.

meshmouse
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Posts: 132
Joined: Fri Jul 11, 2014 10:14 am
Location: Long Island NY USA zone7a

thanks imafan26 -

The only browns I'm really using in any quantity are leaves. Oak, maple, hickory, and beech mostly.

My greens are more diverse - kitchen scraps, grass clippings and now seaweed. I can get more seaweed more easily than I can kitchen scraps or clippings.

You are in Hawaii. Do you use seaweed? If so, how?

meshmouse

toxcrusadr
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I wouldn't think three rinses would be necessary to get salt off the outside. One, or two at the most. Now if you're trying to leach salt from inside the tissue, that's another thing, but everyone says just rinse the outside so I don't think that's an issue with seaweed. One good dunk will remove 99% of salt from the outside. Where does that water go, by the way?

The way you'll know if you overshot on greens is it will get very hot and/or smelly. If it just gets warm or steams and still smells fresh and not putrid, you hit it right on the nose. Observe and adjust.

meshmouse
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Posts: 132
Joined: Fri Jul 11, 2014 10:14 am
Location: Long Island NY USA zone7a

tox -

I think you're right, 3 is probably overkill. I will go to 2. Just wanted to be safe and not screw up my compost pile. The rinse water goes down a hill covered in English Ivy that I would just as soon die, but it has never suffered for it. The English Ivy is a mosquito farm and I am also slightly allergic to it (like a mild case of Poison Ivy). I'll get rid of it one day, but too many other projects more important right now.

So far I've good luck keeping it balanced. It's hot and active and not at all smelly or slimey. At this point I've basically harvasted last years pile and am building a new one in a new and better location for me. It's just getting going but in another month or two it should be up around 140F as it was last year. I think the highest temp was 147F in the center. But it flucuates.

meshmouse



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