Homemade Seaweed Fertilizer
Seaweed — also known as kelp — is a free and organic fertilizer for those living near the ocean. Rich in potassium, it is beneficial to plants, encouraging root growth and vigorous health. Commercial seaweed fertilizers can be purchased; however, making it yourself is so simple anyone can do it.
Collect seaweed from the shoreline and place it in a bucket for transport; several handfuls are all that is required to make five gallons of liquid fertilizer. However, to make the resulting mixture more concentrated, simply add more seaweed to the bucket.
Add water to the bucket and swirl the seaweed around with a waterproof-gloved hand or broom handle. Dump out this first water to rinse the seaweed and remove traces of salt; fill the bucket again with five gallons of fresh water, making sure the seaweed is covered.
Place the seaweed in a cool, dark place — such as a garage or corner of the basement — and let it decompose. Allow the seaweed to soak for several weeks or up to two months. The longer it soaks, the more concentrated the mixture becomes.
Add a small amount of fish emulsion to round out the fertilizer, providing phosphate and nitrogen; combined with the potassium in the seaweed, the liquid then becomes a complete fertilizer.
Make a final mixture of one part fertilizer to one part water; if the seaweed has decomposed up to two months, you can dilute this further to stretch out the amount of fertilizer available. Place the diluted fertilizer in a second bucket and pour it around the base of your plants.
- Plantea: Help From Kelp
- Backwoods Home: You Can Make Your Own Fertilizers
- Vegetable Gardening Gnomes: Liquid Organic Fertilizer
- Earth Easy: How To Use Seaweed to Mulch Your Garden
- Donegal Garden Society: Seaweed for Gardens, Humans and Animals
- Mother Earth News: Free, Homemade Liquid Fertilizers
- Seaweed can be placed directly around the base of plants to decompose quickly, feeding the soil directly.
- Washing the seaweed to remove trace salts is a matter of preference; this step may be skipped.
- Do not put too much fertilizer on the plants; any fertilizer can damage or kill plants if over-applied.
Lori Lapierre holds a Bachelor of Arts and Science in public relations/communications. For 17 years, she worked for a Fortune 500 company before purchasing a business and starting a family. She is a regular freelancer for “Living Light News,” an award-winning national publication. Her past writing experience includes school news reporting, church drama, in-house business articles and a self-published mystery, “Duty Free Murder.”
Homemade Seaweed Fertilizer. Seaweed — also known as kelp — is a free and organic fertilizer for those living near the ocean. Rich in potassium, it is beneficial to plants, encouraging root growth and vigorous health. Commercial seaweed fertilizers can be purchased; however, making it yourself is so simple anyone …
How to Make Seaweed Tea Liquid Fertiliser
Last Updated: November 5, 2020 References Approved
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Seaweed is rich in trace elements and potassium, which makes it ideal to add to compost in its raw state, to work in as a mulch, or to create a liquid fertiliser. This is really easy to do and your plants will be thankful for it; seaweed fertiliser releases about 60 nutrients plants can benefit from.  X Research source Tim Marshall, Composting, p. 71, (2008), ISBN 978-0-7333-2416-1
How to Make Seaweed Tea Liquid Fertiliser. Seaweed is rich in trace elements and potassium, which makes it ideal to add to compost in its raw state, to work in as a mulch, or to create a liquid fertiliser. This is really easy to do and…