Seaweed - a perfect Fertilizer?

Hey,

I am researching Fertilizers.
I heard Seaweed contains nearly all Nutrients that exist! The biggest minus, it is not very longterm Fertilizer, as i heard. (and it stinks, indoorgrower beware)

But im not shure how fast it relases Nutrients IF it is used as Mulch, or Compost instead Waterextraction.
I saw a buyable Seaweedfertilizer that has added something for slow Nutrientrelase.

Would be nice if i could use the Seaweed in any lake around here… How to use it longterm?

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Seaweed In a lake is “Lakeweed” i would guess lol … not sure if it contains the same nutrients. But it should carry some.

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Hmm, the Green Species of Seaweeds , as listed on Wkipedia: https://en.wikipedia.org/wiki/Seaweed , grows in Lakes, and is said to contain Nutrients too.

I mean its listed under Seaweed… I think all Seaweeds gather the Multitude of Nutrients dilluted in Waters

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I’d be interested to see if you could use a basic soil mix or something like FF’s Ocean Forest or whatnot and use ONLY seaweed fertilizers for the duration of the plants life…cannabis, of course. And if this regimen would provide sufficient yield? If you figure it out I’d be sure glad to hear about it.

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Although they are full of nutrients I think most people classify Seaweed/kelp as a PGR not fertiliser due to its high content of hormones like cytokinin.

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Besides the hormones, the biggest thing most seaweed would contribute is potassium, not much nitrogen and little to no phosphate

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@Seamonkey84
from Wikipedia:

Ascophyllum (brown Algae) has long been used as an organic and mainstream fertilizer for many varieties of crops due to its combination of both Macronutrients (N, P, K) and Micronutrients ( Ca, Mg, S, Mn, Cu Fe, Zn. etc. )

So, with this 10 nutrients you cover nearly every Nutrient there is . I recall there are 13 nutrients that exist. Nearly all covered.

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Yes, it does contain everything needed, but not in large amounts. If your composting almost straight seaweed then sure, but adding it as an amendment you’ll likely need to add other stuff still. Kelp meal I have is 1-0.1-2, so yes it has all the micro nutrients and benefits of hormones. But unless you find one with higher levels of NPK, you’ll be using a lot of it. Though MIgardener has a liquid concentrate that is kelp based, but has 9-1-1 ratio. I haven’t tried it yet, but I really like the results I got from his dry fertilizer

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Ok, i can get the Macronutrients (N P K) in almost any fertilizer around the Corner and add them to it.

My Intersse in Seaweed is cause all these rare Micronutrients, wich are not to get around Corner, and not for cheap.

Back to my Question, how to use it longterm?

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Oh, got it, Sorry. I’m in Maine and right against the ocean, I’ve though of using seaweed I can collect on the beach. Through my searching, after rinsing in freshwater, I’ve found You can use it how ever you want really. Dry it and grind it up, Mix it into soil, you can make a tea with it to use as foliar spray or to water with. It you can use it as top dressing too. if you have a lot of it, then keep it whole and use it as the first layer of mulch, right on the soil, then added other mulch on top. There’s even a video showing how to ferment it and use it since it needs to be broken down to supply the nutrients.

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How to use it entirely depends on the source - which will more than likely include feed rates unless you follow through with harvesting that lake Seaweed in which case you might have to tell us when you figure it out!

Their are a metric ton of nutrient companies that offer a Seaweed supplement in their product line. In fact I think you would be hard pressed to find a major that didn’t.

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Does have anyone eprience how fast selvecollected one relases Nutrients? when composted/ when used as Mulch. Has anyone observed it in Experiments?
Thanks, i cant experiment. I run rare Genetics, and dont wanna fail

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getawaymountainseed.com in blue hill ,me makes and sells seaweed fertilizer they make from seaweed. think he only sells commercially though but maybe could pick his brain.

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i found many anwsers here: https://www.globalgarden.co/knowledge/kelp-meal-fertilizer/

they say:
-kelp meal (seaweed dried and cut into Pieces) relases Nutrients pretty slow over 4 Months after mixing into Soil!
-It should be used quickly after harvesting since it decomposites fast ( really? so it decomposes in a dry bag too?)
-they advice to use one Pound per 100 Squarefeet

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but my plants take 8 months to finish…

If left wet when it’s fresh, it decomposes fast. But once dried, it stores no problem, and then is more slow release. Like jerky, even if you rehydrate it, it doesn’t feel or break down the same.

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From what I’ve read, you can’t OD plants on seaweed, so I’m not sure it matters how long it takes. If you use a few different forms it will be used at different times and you can always supplement with some water-soluble kelp in between. I use water-soluble kelp quite a bit through veg. I’m not really convinced that it will have enough Cal/Mag for a heavy feeding Cannabis plant though, but I could be wrong here.

When you say pgr do you mean retardant or regulator as the two are quite differing ?

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The different NPK rates on the various forms of kelp confuse me…i have Down To Earth Kelp Meal that has that lower rate and then I have this Krazy Kelp, I got as a freebie at my Hydro store, and it has an NPK of 1-0-17. Still like @Seamonkey84 said, lacking in the higher concentrations of N and P…

Plants really just need 13 elements. No need to reinvent the wheel; plenty of complete fertilizers on the market.

It makes people feel better to include other elements, but the plant doesn’t care one way or the other.

It’s probably a good amendment in large outdoor plots in nutrient-deficient soils. There’s massive piles of Sargassum all over the Caribbean. For indoor small scale purposes regular fertilizer is a better choice.