Is Fish Waste Compost worth the Mess and Effort?

Project Overview

Project Type: Farmer/Rancher
Funds awarded in 2011: $9,848.00
Projected End Date: 12/31/2011
Region: Southern
State: South Carolina
Principal Investigator:
Dale Snyder
Sweetgrass Garden Co-op


  • Agronomic: hops, millet, potatoes, sunflower
  • Fruits: melons, berries (other), berries (blueberries), berries (strawberries)
  • Nuts: pecans
  • Vegetables: sweet potatoes, asparagus, beans, beets, broccoli, cabbages, carrots, cauliflower, celery, cucurbits, eggplant, garlic, greens (leafy), leeks, lentils, onions, peas (culinary), peppers, radishes (culinary), rutabagas, tomatoes, turnips, brussel sprouts
  • Additional Plants: herbs, native plants, ornamentals, trees
  • Animals: bees, fish
  • Miscellaneous: mushrooms


  • Crop Production: conservation tillage
  • Education and Training: demonstration, farmer to farmer, networking, on-farm/ranch research, workshop, youth education
  • Energy: energy conservation/efficiency
  • Farm Business Management: cooperatives, marketing management, agritourism
  • Natural Resources/Environment: habitat enhancement, hedgerows
  • Pest Management: physical control, mulching - plastic
  • Production Systems: organic agriculture, permaculture, transitioning to organic
  • Soil Management: earthworms, organic matter, soil analysis, composting
  • Sustainable Communities: local and regional food systems, new business opportunities, public participation, urban/rural integration, community services, employment opportunities

    Proposal summary:

    STATEMENT OF PROBLEM What is the problem and how does it relate to, or affect, the sustainability of agriculture in the South? In our coastal region, waste from commercial fishing is readily available. Fish waste is a potential source of nitrogen for composting, and some believe its beneficial properties are superior to those of green waste. On the other hand, many composting web sites include this fish waste on their list of “materials not to add to compost” because of odor and attraction of scavengers. Our goal is to test whether compost from fish bones, heads, and tails increases garden yields. If it does not, then it is not worth dealing with the unpleasant side effects of working with fish waste as a composting material (as long as other nitrogen sources are readily available). In addition we will be testing a composting system that envelops the developing compost in a bio-filter to minimize odor, and uses a passive aeration system rather than frequent turning.

    Project objectives from proposal:

    STATEMENT OF PROPOSED SOLUTION What is your answer to the problem? We propose a comparative trial using test plots to study the problem: Compost preparation: Four of our 4 cubic ft. compost bins will be used. Fish Compost: In two of the bins, composting will be done by alternating layers composed of the following: 1) a 6 inch layer of straw or pecan tree leaves mixed with , 2) a 2 inch layer of fish bones, heads and tails mixed with 1/2 inch of vegetable waste from commercial kitchens. Non-fish Compost: The other two compost bins will have identical construction, but the fish waste will be eliminated, and the vegetable layer increased to 2 inches. Passive Aeration System (PAS): This has been described by Mathur, et. al., and has been used for large scale composting of fish and other odiferous waste in Canada (from a symposium sponsored by Shigawake Organics, Four 2-inch PVC pipes with 1.5 cm holes drilled on one side are positioned along the bottom of the 4x4 ft compost bin, with the holes pointed up and the pipe ends extended beyond the pile. This is covered with a 4-inch layer of finished composts. As compost materials are added as describe above, a 4-inch layer of finished compost is positioned around its edges, so that the column of composting material is enveloped in a cylinder of finished compost. When completed, 4 inches of finished compost is placed on the top, completely enclosing the processing compost in a 4-inch thick 'bio-filter'. Air (oxygen) moving through the pipes is able to rise through the pile. As the pile heats, more cool air is drawn in. As this cools the pile, less air is pulled in (it is an auto-regulating system). The pile is not turned. The fish and non-fish piles will be constructed concurrently so that they will mature at the same time. Test plots: We will test the compost mixtures on 4 adjacent 60 foot rows, prepared as 18 inch beds. One inch of compost will be worked into the surface of each bed. Two rows will have fish compost, and the adjacent two, the non-fish mixture. We propose to grow half of each row in bush beans, and the other half in tomatoes. The plants will be mulched with black plastic, and watered using drip irrigation. APPROACH AND METHODS How will you show or demonstrate that your answer or solution works? What will you measure? Endpoints: 1. Crop yield measured by weight and volume of produce. 2. Quality of produce, a subjective endpoint. This assessment will be made in a blinded fashion. Two of our co-operators, Joseph Fields and Roger Francis, will inspect the test plots in mid season and again at the time of harvest without knowledge of which compost was used. 3. A test of the passive aeration system. The question is whether this technique can be adapted to small scale use.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.