Making Organic Seaweed Fertiliser at home

Making Organic Seaweed Fertiliser at home

Having a home garden is a great idea in these crazy times with all the shortages of basic foods and the high prices of fresh vegetables  elevating at an alarming rate.

Depending on a persons circumstances as in the property they reside in, having an area where you can grow your own food is rather ideal. I have always had some sort of crop growing, I'm blessed with green fingers, that just crave being in the soil tending the children of mother nature.

On our property which is a Kiwi Quarter in size, we have a large garden space to grow not only flowering plants & fruit trees but loads of fresh produce for our business and personal consumption.

We are Certified Organic by Organic Farms NZ so only use organic methods on our property. Over the years I have developed many skills in organic growing. The thing I love about organics is you feed the soil and give it love and it feeds you and gives you love.

It is quite easy to make your own seaweed fertiliser at home in your back yard if you live near or by the sea. Seaweed is the best complete organic fertiliser you can get, it is full of vitamins and minerals as well as loads of micro amd macro nutrients.

It pays to check that you are allowed to collect seaweed from your beach as there are restrictions in some areas.

It is just a matter of collecting a bag of fresh seaweed, washing the salt and sand off and cleaning out any debris, then soaking in fresh water for a month, then it is ready to use. The seaweed is then given more water and soaked again, you can get 6 months worth of fertiliser out of a bag of seaweed.

What you will need to do this is, 2 x 5-10 litre buckets the same size that fit neatly inside each other and they need well fitting lids. One bucket neeeds to have lots of small holes drilled in the base. This bucket will sit inside the other bucket and will hold the seaweed.

Initially it will take a few hours to collect and prepare the seaweed but once it this done it become hands off.

Like I said it is quite easy, it will stink to high heaven when it is done so I suggest using gloves when diluting the solution to avoid it getting on the skin as it is hard to get the smell off.

Plan to do this on a day that you have plenty of time as it will take a few hours to do, it could be a project that the whole family can get involved in.

The first thing is to get your buckets, then go to the beach and collect the seaweed, any seaweed that washes up on your local beach will do. Do not take seaweed that is still in the water this will upset the delicate natural ecosystem of our ocean.  The seaweed that has been washed up on the high tide line is what you need. I suggest be mindful of Blue Bottle Jellyfish if your beach is subject to these.

Now you need a space to do the cleaning and washing, you will get better results if you cut the seaweed up into smaller pieces, this will help with the extraction/infusion process.

The seaweed once cleaned of debris and cut goes into the a large bucket or bin to be washed for removal of salt and all the sand. Seawater is not good for your garden so this is a very important part of the process.


Once you have prepared the seaweed it is loaded into the bucket with the holes in the bottom and this bucket is then placed inside the other and filled to the brim with water. put the lid on the bucket and seal, some of the water may spill over but the bucket should be full.

Find a place to store your fertiliser out of the way and then mark the calender or diary so you know when  to harvest.

In 4 weeks it is ready to harvest, be sure to wear gloves and don't spill any on yourself.

Remove the lid and lift the top bucket out carefully, allowing all the fertiliser to remain in the bottom bucket, you should have about 1/2 to 3/4 of a bucket of very stinky strong fertiliser.

This will need  to be transferred into another container/s for storage and distribution in the garden.

Then you put the seaweed bucket back in the bottom bucket and refill with water to make your next batch.

This fertiliser will need to be diluted 1 part of fertiliser to 2 part of water for watering into the soil. For a foliage spray, I recommend 1 part to 10 parts as it is strong and you don't want to burn the foliage.

Well that is it really, now you know how, it is time to get too it and give your garden some love so it can love you back.

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