Seaweed is a fantastic soil or compost ammendment
What is it?
Seaweed is a general term for any of the multi-celled ocean algae.
What is the primary benefit?
Seaweed is a great source of organic matter for our compost and our soil. It is full of beneficial trace minerals, plant growth hormones, and fully-chelated (that means readily absorbed) micro-nutrients. Depending on where we live, we may have access to large amounts of seaweed. Currently, we are just a hundred yards (90 meters) from the rocky Azorean beach. The recent storm deposited literal tons of seaweed on the shoreline (read this article I wrote about it).
How is it used?
Seaweed can be used directly as a mulch. It provides all the benefits listed above, but it also repells snails and slugs – natural salt content and dries out with tiny jagged edges that they despise. Just keep in mind that there will be a fishy odor from the seaweed as it breaks down, some are have a stronger odor than others. The salt content is usually not enough to cause too much issues with your soil, especially if you live where there is a decent amount of rainfall; most places with plentiful access to seaweed have sufficient rain. However, if you are concerned, you can rinse the seaweed out for a few minutes with clean water before application.
Seaweed can be composted. This is a great way to incorporate all the seaweed’s benefits into our soils. Just treat it as any other “green” material.
Seaweed can also be used to make an emulsion-type fertilizer. There are many recipes for creating this, but the general principles are the same. Take a bucket and fill it halfway with seaweed. Next, fill it up with water. Let it sit anywhere from 2 days to 2 months. Keep in mind that this can get stinky! The longer it soaks, the more concentrated it becomes. If it only soaks for a few days, then the water can be sprayed directly on plants as a foliar fertilizer. If it soaks for a long time, then dilute the seaweed liquid with water, and then apply. Dilute more if the seaweed soaks longer, and always err on the side of applying too little.
Application:
Add fresh seaweed to your soil or compost directly.
Add fresh seaweed to as mulch around plants.
Do not use seweed to mulch garden paths – will become slippery if wet, and it shrinks when dry and is not too effective.
Composition:
NPK Ratio:
- Dried/Composted Seaweed: 1.1-1.5/0.75/4.9
- Fresh Seaweed: 0.2-0.4/0/0
A Note About Collecting Seaweed:
Only use seaweed that has washed up on shore. Avoid cutting or pulling up established, growing seaweed. Sustainability matters.
A GENERAL NOTE ABOUT FERTILIZERS:
Always test your soil before adding any fertilizers. We can easily damage our plants and the soil by indiscriminately adding soil amendments
Original Article Here