The next time you find yourself preparing to throw out spoiled fish or fish remains, stop for a second and reconsider. Fish makes a very good natural fertilizer for nitrogen and trace minerals. In fact, it works so well that many Native American horticulturalists buried a fish at the base of each crop plant. Check out the video below!
How to Use Fish Scraps as Fertilizer
You can grind your fish parts up to make your own fertilizer. We recommend using a hand grinder or stick blender rather than your kitchen blender. It’s easier to clean and can be used as gardening tool and not the kitchen. Then work it into the soil, or you can bury chunks of fish at the roots of your plants. Be aware, however, that dogs and some wild animals are fond of strong smells, and may dig up your garden if you use fish as fertilizer. Be sure to bury it deeply, or fence in your garden.
If you don’t want to bury fish scraps, try making your own fish emulsion. There’s a link below.
Or, add ground up fish bones and skin to your compost pile, adding nitrogen and trace minerals to your compost. Keep in mind fish scraps can increase the chance pests will find your compost. Here’s a detailed PDF from Louisiana Cooperative Extension Service: Composting: A Disposal Method for Fish Waste. This is a great resource if you know an angler or fish yourself and want to set up a compost pile for fish scraps.
Where to Find Fish Scraps
If you are not an angler, don’t worry. There are many ways to find fish in your community.
Try a fish market and ask for their scraps. Most will be happy to give them to you. It’s just like asking the coffee shop for their used grounds.
If there is not a fish market close by, try a high end market, grocery store or restaurant with a great seafood selection and see if they have any wastes. They are more likely to clean their fish and have scraps or even fish heads.
Scraps you’ll want to ask for include: intestines, liver, gall bladder, heart, fins, tail, scales, fish heads/gills and bones.
Want to learn more about using fish as fertilizer?
Make Your Own Complete Fertilizer from University of Alaska Fairbanks Cooperative Extension Service: See how to make fish emulsion here.
Organic Fertilizers: Fish Emulsion from Colorado State University Extension Program
Creating Community Gardens from Northwest Indian College Cooperative Extension: Great information on building soil with fish and shellfish.