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How to Make Fish Fertilizer

By Tammy Curry ; Updated September 21, 2017

Fish fertilizer is not to be confused with fish meal. Fish fertilizer is made from composted fish. Fish meal is processed fish parts from processing fish for human consumption. Fish fertilizer is a valuable organic fertilizer that is high in nitrogen and phosphorus, two essential nutrients for healthy plant development. You can canned or fresh fish to make fertilizer. Canned fish contains preservatives not found in freshly caught fish. When possible use fresh fish to make your fertilizer. Fish fertilizer is applied as a liquid fertilizer to lawns and gardens.

Cut the fresh fish into medium size chunks with a large, sharp knife. Cut fish will compost faster than whole fish.

Fill a bucket half way with a mixture of sawdust, leaves and grass clippings. Add the fish chunks and 1 to 2 ounces of unsulfured molasses to the mixture. Molasses masks the smell of decomposing fish and provides nutrients for the microbes that break material down into compost.

Mix the contents of the bucket with a long handled barbecue fork. Add 1/2 gallon of water to the bucket and mix thoroughly. Close the lid. Stir the contents of the bucket every two to three days. Let it decompose for two weeks.

Dump the contents of the bucket into a large square piece of burlap. Pull the corners together and secure with jute twine.

Fill the 13-gallon trash can 3/4 full with water. Insert the burlap filled with the fish compost into the water. Steep for one to two weeks in the water.

Remove the burlap bag. Fill the bottle of the garden spray hose attachment with liquid fertilizer. Attach to the garden hose and set the rate to 1:5 (equivalent of 5 gallons of fertilizer to 25 gallons of water).


Things You Will Need

  • 5-gallon bucket with lid
  • Sharp knife
  • Fresh fish
  • Unsulfured molasses
  • Sawdust
  • Leaves
  • Grass clippings
  • Long handled barbecue fork
  • Burlap
  • Jute twine
  • 13-gallon trash can
  • Fertilizer spray attachment for garden hose
  • Garden hose

About the Author


Currently residing in Myrtle Beach, SC, Tammy Curry began writing agricultural and frugal living articles in 2004. Her articles have appeared in the Mid-Atlantic Farm Chronicle and Country Family Magazine. Ms. Curry has also written SEO articles for textbroker.com. She holds an associate's degree in science from Jefferson College of Health Sciences.