According to the book 'Food Power from the Sea', fish was used as a fertilizer in Europe as far back as the middle ages. The technology has changed - we now have liquid products that are easier to apply and more efficient - but the principles are the same.
I get a lot of questions about what to use for organic lawn care. Lawns are not all that different than the plants in your garden, but we do expect them to do more, and our ability to improve them is a bit more difficult.
In terms of expectations, we want them to resist a fair amount of compaction, we often want them to grow where they probably wouldn't grow if they had a choice, and we want to be sure they do not contain too many of their weed friends who actually make them much healthier. It's quite an unnatural situation, but we've come to love them and for good reason - they have many benefits.
In terms of our ability to improve them, things happen more slowly. In the garden, we can throw on a hole bunch of compost and organic matter and get things moving quickly. If we're dealing with an established lawn, we might be able to use 1/2" of compost a year, and we can't use many leaves either, unless they're chopped up finely. Transitioning a lawn takes some time.
I can't get into everything that is involved with lawn care here, but in this issue, I'd like to point out the benefits of using a liquid fish hydrolysate. Before using fish, I always recommend mycorrhizal fungi and effective microorganisms as being the most important microbial products to bring into the lawn, but fish has an important role. Incidentally, all of these benefits apply to the garden as well.
It is important to use a hydrolysate and not an emulsion. I explain the difference here: fish hydrolysate vs fish emulsion.
If you are dealing with a lawn that is hooked on chemical fertilizers, or doesn't have much organic matter, or has had the clippings removed regularly, fish is an incredible transitional product (while you're also focusing on improving the organic matter content of the soil and leaving the clippings).
Perhaps most important, it brings a small amount of high quality nitrogen that the turf plants can't get in the above situation (nitrogen is held in the organic matter, so if you don't have enough OM, you don't have enough nitrogen). Unfortunately, chemical forms of nitrogen cause a long list of "side effects" that ruin the soil. The nitrogen in fish is natural and available.
Also, equally important but not generally discussed, fish brings in phosphorus, which is often lacking in our soils (characterized by broadleaf weed pressure in the lawn). Some of this phosphorus is organically bound and soluble, so it is easily used by plant roots, whereas rock sources of phosphorus are mostly tied up and need strong microbial action (especially mycorrhizal fungi) to make it available.
It also has a broad range of other nutrients and is full of delicious things, some of which I have very little knowledge of their exact role. These include gelatin tissues, nonprotein nitrogenous units, protomins, carbohydrates, and enzymes.
I am always thinking about the sustainability of fish products, and every few months I inevitably find myself checking back into it, to be sure the particular product I carry is okay. Here is some information I received the last time I checked:
- GPB/Pacific Natural only uses wild fish that are sustainably caught under the auspices of Fisheries and Oceans Canada.
- In response to market and consumer demand for third party certification of ‘sustainable fisheries’ and their products, many BC fisheries are undergoing certification by the UK based Marine Stewardship Council (founded by the giant Unilever group and the World Wildlife Fund) many years ago.
- GPB/Pacific Natural will only use fish byproducts from fish that are currently deemed sustainable by Fisheries and Oceans Canada, and in future, only from third party certified fish species.
- One of the cornerstone species of this fish hydrolysate are byproducts from the BC dogfish fishery. This fishery is currently undergoing a third party assessment by the Marine Stewardship Council, at a cost of more than $100,000 that will be completed in 2009.
- Other fish species we use are in the early stages of Marine Stewardship Council assessment.
- The BC groundfish industry (the source of the fish used in this product, including dogfish), is without question the most stringently monitored and accountable fisheries groups in the world today.
Castle Pines Golf Course uses it as the primary source of nitrogen on their greens! Don't let the 2% N content fool you. It's the quality that counts. They also use it on their fairways. Read about that here: Liquid fish hydrolysate on turf
If you're trying to decide which biostimulant to bring in with your EM for turf, try the liquid fish hydrolysate, once a month, at approximately 430ml/1000 sq ft. Even better would be to cut the application rate to 180ml/1000 sq ft and do it weekly, if at all feasible.
Mix it with your effective microorganisms, which will help control the slight odour and make the fish more available to the grass.