Natural fertilizer - seaweed

[Janne]

As you probably know, I live on an island south of Cuba. My house is situated on a canal connected to the sea. Filled in mangrove, so incredibly bad soil. If you can call it soil!
This time of the year we get lots of floating seaweed into the canal.
As we are in the process in making a growing area ( tomatoes mainly) we have to improve the soil somehow.
We got some growing bags, but they are quite expensive, so I got the idea to do what has been done historically all around the world, dig down seaweed.
The last few days me and son have been scooping up as much seaweed as we can reach from our dock.
Washing out the salt water, the rain help too.
We have now maybe 10 large wheelbarrows.

Has anybody else tried this?
Is t enough to just dig it down in its natural state?

 

[beachlover]

I use it all the time on my allotment and garden as I am walking distance from the beach. To be honest, I don’t even wash off the salt. I also learned a neat trick from a friend on the allotments and that is to spread it and spread it thick, but before digging or rotavating it in, run over it with a lawn mower on as low a setting as you can get away with to “mince” it up a bit. ideally it should have been done over the winter and early spring though, so it would be a bit late to do it here in the UK and expect real benefits this growing season.

 

[Toddy]

It has a very long provenance. It provides excellent minerals, etc., it was well used for the misleadingly named Lazy Beds which were made where the soil was thin or poor.
https://thecroft.wordpress.com/2008/07/06/lazy-beds/

Have you thought about the Hugelkulture beds though ?
https://www.permaculture.co.uk/articles/many-benefits-hugelkultur

They don't need so much soil just anything organic that will hold moisture and allow the roots to grow down into it. Brash, cardboard, paper, shredded cottton, etc., they all work.

M

 

[Dogoak]

If you get a chance watch the film, The Field, starring Richard Harris, excellent gritty film and relevant to your question.

 

[Janne]

Toddy, interesting concepts!
The area we plan to use is only about 5 x 5 meters, so I am a bit limited.

My thinking is to bury a fairly layer of the seaweed about 15 cm down, compress and cover with the crappy 'soil' that has been mixed with a product they call 'Top Soil' which comes in bags, about 50% crap and 50% 'Top soil"

Will see if I can find the movie online. Love Richard Harris.

Edit: I think we collected about 5 large wheel barrows, heaped.
Will also use some as a weed suppressant in pots. We have 4 Lime trees in pots.

 

[Robson Valley]

There are two more values to me mindful of.

As any soil settles, the water-holding capacity is diminished.
It saturates very quickly and the rest might be runoff and erosion.

Anywhere on earth, you recognize trails by a distinct lack of vegetation, right?
Why the barren ground? It is not the scuffing of foot traffic.
Actually what's happened is that the soil compaction leads to a lack of air in the soil.
Plant roots need oxygen for respiration just as we do.

As a note added in proof, heavily used grasses (golf courses for example) will use a "plug cutter" in turf management.

All the seaweed rubbish will aid in "fluffing up" the soil bed for both air and water.

 

[Hbc]

Sorry for the late reply to this thread but I have a good excuse, as a new member I've only just found it
Seaweed will be a great soil improver as you know it has been used all over the world to improve poor soils for a very long time. Don't stop at seaweed though anything organic will rot down and improve it too. Veg waste from the kitchen, lawn or hedge cuttings from the garden, previous crop residues, pet (or your own ) poo are probably the easiest and most obvious ones but anything will help. Compost it first and spread that if you prefer it might be better to start off with if the soil is really thin poor soil.
One thing that is very underestimated and not that well known is how important growing roots are to improve soil and keep it 'alive'. Try not to leave bare soil if you possibly can avoid it. Soil loses a lot of organic matter and natural structure by not being covered by green growth. Plant something else for cover until you are ready to plant it again in spring. That is if your climate isn't suitable for cropping all year? Something cheap and simple is all that's necessary here we would use a brassica of some sort after a cereal crop for example (not gardening but you get the idea) that would be grazed off before spring by livestock but you could easily kill off a cover crop in a garden with an old carpet of anything else that will smother the plants and block out light but still allow rainwater through.
People have forgotten that soil is a 'living' thing full of complex organisms and fungi and bacteria and loads of other stuff that we don't fully understand. It needs feeding with organic matter and root exudates from green living plants to be really truly productive healthy and sustainable.
When you get a good mass of roots growing in your soil for as much of the year as possible and get plenty of organic matter in it you should see things start to really improve in a relatively short amount of time.

 

[SCOMAN]

Once the Irish had been evicted from the fertile lands of the east coast they were put over to the rocky poor soil of the west coast and they had to 'win' the land back. Seaweed was available and free and was used extensively. It was usually put into a running fresh water stream to get rid of the salts chopped up to some degree then turned into the soil. As Hbc says mix as much organic matter in to rot down and you should be laughing.

 

[Billy-o]

Also, it is good for the complexion. Girdle your limbs and torso with it ... lightly beating oneself with kelp stalks (in a recognisably Scandinavian manner) ... also improves the circulation.

Which brands is it you have in your locale, Janne? Any eatable ones?

 

[Janne]

It is mainly the Sargassum. It floats in a couple of times a year, in thick floating mats.
After a good storm we can also get one that looks like thick grass, which normally grows in the shallow sound here.

I am not sure the Sargassum is terribly palatable. Might be nice to get whipped with, in a good oldfashioned Swedish style. Sometimes it does feel like a sauna here!