While fish emulsion fertiliser is an effective concentrated organic liquid fertiliser used in flowerbeds and vegetable gardens, some gardeners prefer alternative substances. That preference may be because fertiliser made from emulsified fish parts smells somewhat like dead fish. Others object on principle; vegans, for example, don’t care how natural or organic fish emulsion is. They would rather use an effective organic fertiliser that’s strictly vegetable and mineral.
Hydrolized Liquid Fish
Enzymatically digested hydrolyzed liquid fish fertilisers depend on enzymes rather than heat and acids to digest the nutrients in fish wastes, a process that retains more of the proteins, vitamins, enzymes and micronutrients than fish emulsion fertiliser. Hydrolyzed fish has slightly less nitrogen than fish emulsions, but otherwise offers more nutrients.
Fish Meal or Powder
If it’s the “liquid fish” that’s objectionable, dried fish fertiliser alternatives are widely available. Fishmeal is heat processed and finely ground, and offers 10 per cent nitrogen and adequate amounts of phosphate and potash. Worked into the top 12 inches of soil that’s soon covered with thick mulch, fishmeal delivers plenty of “underground” plant nutrition without the stench. Dried fish powder, even higher in nitrogen, can also be mixed as a water soluble foliar fertiliser.
Fish, Bones and Wood Ash
University of Alaska Extension offers a do-it-yourself complete fertiliser recipe, if it’s the commercial nature of fish emulsion fertilisers--or the high cost of shipping to remote locations--that gardeners find objectionable. The key ingredients for home-grown fertiliser are fish waste for nitrogen, burnt animal bones for phosphorous and wood ash for potassium.
Kelp, Alfalfa and Phosphate
If using liquid fertiliser is not essential, you can blend an effective organic fertiliser acceptable to vegan farmers and gardeners by combining alfalfa meal or pellets--high in nitrogen--with rock phosphate for extra phosphorous. Kelp powder or liquid kelp offers micronutrients.
A wide variety of commercial organic fertilisers is available commercially, though these tend to be more expensive than homemade blends. Some are liquid and some are granular. Some contain animal ingredients such as fish waste or bat guano, and others are derived completely from plants and minerals. Order online from reputable companies if there aren’t any organic fertiliser suppliers nearby.