March 22, 2023

4 ways I use sea weed in the garden

A free resource

We were away by the coast last week and so I collected a bit of kelp seaweed for my garden as there was loads on the beach that I walked every day. Kelp is a sea weed that can be found in abundance on most coast in the UK. There are lots of uses for sea weed and it is a great free natural resource.  Some sea weeds can also be eaten (eg. kelp can make a good stock)  or used to make beauty products, but I just wanted some for the garden.  It is a brilliant way of adding nutrition to my plants as it has lots of trace elements in it and potassium and magnesium.  In fact it has a lot of the things that you would find in  fertilisers that you can buy in the shops.  I collected it in a black bag and took it home placed in the bag in a bowl as it was only a three hour journey.  My car did not smell at all.  When I got home I rinsed the seaweed as too much salt on the garden is not good for it.  This is what I did with it.

Put some in my compost

I added some to my compost bin, but not too much or else it would make my compost slimy.  I added a load of card board loo rolls and so small wood branches to ensure that I was adding enough brown material to balance my compost.  If you are making a raised bed you could also put a layer in that under carboard or other brown material.

As a mulch

I have saved some to use as a mulch around my plants so that the goodness will be taken by the worms into the soil and it will shade the soil and stop it drying out.  The goodness will also be slowly released  into the soil and it will reduce weeds.  I have heard that it is good for mulching and earthing up potatoes.  Apparently onions like it as well and it helps them grow more quickly at the start of the season.

Make a liquid fertiliser

I cram seaweed into a bucket until it is a quarter full and then top it up with rainwater.  I put a  plastic old smaller lid on top of the seaweed and a stone used as a weight on top to keep the seaweed under the water. I  also put a lid on top of the bucket as it can smell a bit.  I mix it a couple of times a week and it is ready in about 3 months and so mine will be good for June when I am planting lots out in their containers.  To use I dilute one part of the seaweed tea to 3 parts water.

Dry out to add to soil

The rest I am going to dry out in the sunshine and then crumble it up to add to my soil as I replant my plants in big pots, and this will improve the condition of the soil.

Check before foraging

In some places foraging for seaweed is not allowed and so it is important to make sure that you have checked the bye laws before you take any. It is also important to make sure that there are no sewage outlets nearby or pollution.  I don’t collect sea weed that is still attached but just that which is washed up on the shore.  I would only take it if it was plentiful as it is often used as a habitat for some micro organisms, and I don’t take it near the shoreline.  There had been storms whilst we were away and so the lonely beach was littered with it.

I love any thing that is free and love using nature’s natural resources.  Does any one else forage seaweed or use it on their garden?

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  1. Linda March 23, 2023 at 6:18 pm - Reply

    I have never done this but it sounds like a great idea. As a child we lived on the North Devon coast and seaweed – laver – was a real treat. My Mum bought it at the Friday market along with hogs pudding. These are delights from my childhood sadly unavailable where I live now.

    • ToniG March 25, 2023 at 8:29 am - Reply

      Aww bless you, though most things are available to buy on the internet. Yes I tried a lava bread once. I am not sure if it is the same. I hope my post brought back some happy memories

  2. Katie Naden March 23, 2023 at 8:48 pm - Reply

    Brilliant thank you my brother who lives on Islay always uses it on his Croft veg patch. I didn’t know there were byelaws covering removing seaweed. Where do you find the local rules ?

    • ToniG March 25, 2023 at 8:28 am - Reply

      You find out local bye laws by asking the local council. That is a great free resource for your brother

  3. Maggie March 25, 2023 at 8:23 pm - Reply

    Yes, I put seaweed straight onto the beds where I am going to plant potatoes. It’s sad to see how much plastic there is in it now, especially fishing lines/nets. You can also put it in a bath – good for the skin! (Then add to the compost!)

    • ToniG March 26, 2023 at 9:15 am - Reply

      Thanks. I have never thought of putting it into the bath

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