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Rediscovered: The Lost Seaweed Fertiliser

Hi everyone,

I've just 'rediscovered' 2 sealed containers of seaweed fertiliser I made up last year, but forgot about..

I'm guessing the mix will be somewhat anaerobic by now ;-)

Will it be possible to use it this year, if the liquid is aereated with a small fish tank air pump I have lying around?

And will it still hold some of the groovy garden goodness I was looking for last year?

Thanks in advance


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Joined: Sun Apr 21, 2013 12:06 am
Location: Ocean Springs, MS

As long as you give it a healthy stir before your use it it will be fine. From what I understand the longer you leave it the stronger the fertilizer will be. I'm guessing the aerator won't hurt but is not a necessary step.
Also, I'm not sure what you mixture is exactly but here is my source:

DIY Seaweed Liquid Fertiliser
Not sure if many people here use seaweed as a fertiliser, I it's for outdoor grows mainly but as an organic fertliser its a great thing to add to plants. The best way to use it is in its dry form as a mulch or as a foliage spray in liquid form.

This liquid form is very easy to make so I thought I'd share it, it takes a bit of time but once you're done, you're cruising.

Go down the beach and collect a ton of seaweed, check your local laws you don't wanna get busted for raiding the beach, although I'm sure not many of us care about that here. Collect as much as you think you can fit into whatever container you decide to use. You can use any size container, just remember, the bigger the container, the more fertiliser you will have.

Take your seaweed home and give it a rinse to remove excess salt. Next fill your container 2/3 of the way full with water. Tap water is fine since its going to be left sitting for a while anyway. Next grab your seaweed and shove as much in the container as you can without the water overflowing.

Next simply cover your container and let mother nature take care of the rest. Giving it a stir once in a while will help spread nutrients into the water evenly but really as long as you give it a stir before you decide to use it, you'll be fine. Leave it for a minimum of three weeks and then it's good to go. Just remember, the longer you leave it the stronger your fertliser will be.

Seaweed is high in Potassium and is also used as an organic pesticide so use a spray bottle and give the leaves a misting every few days in the flowering cycle if your plants need the extra potassium boost.

Also here is the link to the forum from which the info came. ... liser.html

Mods I hope this is within the rules and if not I totally support my post being removed.
Also my apologies if I am breaking any rules.

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Joined: Tue Apr 23, 2013 5:50 am

Hi Rodger,

thanks for the advice. You said exactly what I wanted to hear!! :D

Unfortunately the closest seaside to Amsterdam is miles and miles of sandy beaches and not the best place to collect seaweed.

But what we do have here is a fairly extensive Chinese district and, if there is one thing about the Chinese it's that they love eating seaweed. So I popped into one of the supermarkets there and bought a big ole bag of the stuff, purely to create this wonder-addition for the plants.
The weather was so poor last year, with so much endless rain that I should have went one step further and planted some paddy fields for a rice crop instead! ;-)

Again, thanks for the advice Rodger. it's very much appreciated.



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Actually, I think I'll be brew it into a 'tea' with some worm compost I've had maturing this past while...

That should make for a happy garden! :D

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Location: Boynton Beach, Florida

You should try something like 1 cup of Worm Castings, a 1/4 cup of steer manure, 1 Tbsp of the Liquid Kelp you've made (make sure to shake the container well to get the particles of seaweed). If you have any organic fertilizers such as kelp meal which is good for 1 Tbsp in this mix, or High N Guano at 1 Tsp, Azomite(Rock Dust) 1/8 of Tsp, 1 Tbsp of Alfalfa Meal, 1 Tbsp of Feather Meal, and 2 Tbsp of Natural Mollasses.

Try to add as many ingredients I have listed as you can in the tea in the amount I listed per gallon of water (if it says 1 Tbsp means 1 Tbsp per Gallon of Water). The more of the ingredients you can provide to your garden the healthier it will be and the lusher the growth especially if growing fruits and vegetables. The worm castings, steer manure are mainly considered innoculants and the Liquid Seaweed provides growth enzymes and some nitrogen but you won't get much else from you tea but nitrogen without adding some other ingredients in sparingly

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