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DIY Kelp Fertilizer

DIY Kelp Fertilizer

Natural Fertiliser - Kelp  

If you're lucky enough to live by the ocean, you are right next to the most abundant source of free fertilising potential - seaweed. After a high tide, or a stormy night, it's common to find the beach strewn with slimy, fresh weeds, and this is what you're after - nothing too smelly, nothing too dry.

For some beautiful liquid fertiliser, all  you need do is fill a bag or waterproof container with as much as you can manage and hose it down at home to wash off any excess salt.

Throw the kelp into a decent sized bucket and then fill it up with water, completely covering the seaweed.

Place the bucket in a cool, dark spot (preferably one that won't fill your house with the soon-to-be-apparent smell of decomposing kelp) and leave for anything from a few weeks to several months. The longer you leave it, the more concentrated it becomes. It's ready to go from around the time it stops smelling of ammonia.

Dilute by about one cupful to one large watering can (or less - too much fertiliser can kill your crops!) and distribute around the base of your plants. Otherwise, further dilute the solution and spray directly onto the greenery - a high concentration sprayed on the leaves may cause scorching so record your ratios until you find optimal ones!

Kelp fertiliser is the most wonderfully nutritious stuff:

  • Releases up to 60 nutrients that benefit plants
  • Increases plant growth
  • Increases fruit yield
  • Increased resistance to pest and fungal attack
  • Low cost
  • Low environmental impact
  • Can be used as a rooting solution
  • Alginates keep soil moist at ground level

Be absolutely certain you're not collecting seaweed in a polluted area, or downstream from one, and also that you're not breaking any laws by gathering it.


Image: Alybaba/Shutterstock

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