I was asked by Dr. Linda Chalker-Scott to look up some information in order to answer a recent comment and question on a previous post.
Paraphrased, the question is, “… are there any verifiable “organic” fertilizers that can be guaranteed to be made from 100 percent non-GMO sources.”
First off, let me state up front that the whole “Non-GMO” labeling effort is pure marketing. There is no evidence to suggest products that come from genetically engineered crops are any different than crops made from other plant breeding methods. The body of evidence in fact suggests they are as safe as their conventional counterparts, and have some excellent benefits to farmers and consumers from an economic and environmental standpoint.
Having gotten that disclosure out of the way, and assuming that price is not a factor, it turned out to be an interesting question to answer.
“USDA Certified Organic” fertilizers would be problematic, since there are exceptions to the organic standards, which allow manures fed GE crops to be used.
Similarly, oilseed meals like cottonseed, soybean meal, etc. also can be certified organic, even though they come from genetically engineered crops.
ALFALFA MEAL
One possible alternative in that category is alfalfa meal, since genetically engineered alfalfa is currently grown on only 13.5% of alfalfa acreage, whereas in the case of cottonseed, soybean, sugar beet, and corn products, the rate of adoption of genetically engineered crops is well over 90% of U.S. acreage.
Only about 13.5 percent of harvested U.S. alfalfa acreage is genetically modified, compared to more than 90 percent of corn, soybeans, cotton, canola and sugar beets acres, according to a new USDA report that cites 2013 farmer surveys.
It appears likely the percentage of genetically engineered alfalfa will continue rising, though: Roughly one-third of newly seeded acreage planted that year was of a biotech variety resistant to glyphosate herbicides, USDA said.
Farmers have been slower to adopt genetically engineered alfalfa partly because it’s a perennial crop that stays in the ground for roughly five years, said Dan Putnam, an alfalfa extension specialist at the University of California-Davis.
It would be incumbent upon the buyer to ask, however, if the alfalfa meal came from a grower who does not use genetically engineered alfalfa, and whether or not the supplier of the alfalfa meal guarantees that.
MANURES FROM LIVESTOCK FED ONLY ORGANIC FORAGE
“Demeter USA” … the private certifying entity that guarantees “Biodyamic” preparations does require that any manures come from livestock fed only “USDA Certified Organic” feed. So manures that carry that seal should satisfy the question.
As an aside, here is Dr. Linda Chalker-Scott’s literature review of “Biodynamics” and why that certification has little science to recommend it.
Further, finding the product would be difficult, since it is primarily produced on-site at certified Biodyamic farms, and used there.
SEAWEED FERTILIZERS
Next products that might qualify are seaweed, or kelp products. There are no genetically engineered seaweed/kelp products I’m aware of. However, there are real concerns about the sustainability of harvesting seaweed and kelp from the wild.
Dr. Linda Chalker-Scott wrote about them here:
The ecological impacts of increased seaweed harvesting are currently under investigation and the possibility of significant ecosystem damage is real.
There is however, some interesting research and startup companies that are farming seaweed and kelp for a variety of potential uses.
I can’t however, find any products available for the home gardener that are sourced from this effort. Still early.
So, when it comes to seaweed/kelp products, you’ll have to (again) ask a reputable supplier to answer the “sustainable” question.
BAT GUANO
In a similar vein, “Bat guano” products would also qualify as “non-genetically engineered”, but the sustainability question also comes into play. How is it harvested?
I can’t deny that it’s a great fertilizer, but if you want to use an organic fertilizer why not at least consider one that is renewable instead of one that is from a limited resource and which may cause harm to a unique ecological system?
SEAFOOD BY-PRODUCTS
Fertilizers made from by-products of the seafood and fish industries, assuming they don’t come from aquaculture farms, since the livestock feed for those operations could be sourced from genetically engineered crops, do have a history.
Two links (there may be others, but these seem sufficient for now), a comprehensive review of products (including fertilizers) from the Alaska seafood industry, put together by Oregon State University …
Fish Fertilizer Product Descriptions
Fertilizers are characterized by their Nitrogen-Phosphorous-Potassium content (N-P-K). Therefore all fish material will have some fertilizer value since fish contain protein which is Nitrogen,
the bone contains Phosphorous and the flesh and bone contain Potassium. Generally, fish products are re-allocated to fertilizer use for any number of reasons including quality too poor for feeding, volume too small to convert to fishmeal and oil, and an available agricultural market in the vicinity of the waste material.
And a similar document put together by Michigan State University about the use of fish by-products for other uses.
In an effort to help the Michigan fish processing industry find better solutions to handle fish processing waste materials, a project was initiated to determine the viability of composting fish waste.
CHILEAN NITRATE
There is a mineral product called Chilean Nitrate or Nitrate of Soda that is mined from a desert in northern Chile that is allowable for use under the standards for organic production in the U.S. However, it is not allowed for use under Canadian, or international organic standards, and a change to prevent its use under U.S. standards is still pending. Up until 2012, this was the wording for its use.
Sodium nitrate, also known as chilean nitrate, cannot account for more than 20 percent of the N requirements of organic crops in the United States.
Its use is also prohibited by the International Federation of Organic Agriculture Movements (IFOAM) and most other standards for organic production outside the United States.
After 2012, the 20% restriction was dropped in the U.S.
The expiration of the current notation will effectively mean that sodium nitrate may be used in organic crop production without a specific restriction on the amount used: however, producers must continue to comply with all requirements of the soil fertility and crop nutrient management practice standard.
Although the National Organic Standards Board (NOSB) recommended that sodium nitrate become a completely prohibited nonsynthetic substance, the NOP has not issued rule-making to carry out this recommendation as of yet.
FEATHER MEAL
A by-product of the poultry industry. Is it from poultry fed only non-GMO feed?
LOCALLY PRODUCED
The final piece of the puzzle can be found (only partly in jest) in Dr. Jeff Gillman’s post about a cheap, locally available source of Nitrogen.
You’d be saving yourself the cost of fertilizer, saving the environmental cost of shipping the fertilizer you might otherwise purchase, saving water, and you’d have something unique to tell your gardening friends about. Win – win situation as far as I’m concerned.
In summary, I don’t buy into any of the fear-based marketing of products that come from genetic engineering. There may be (at this time) sources of alfalfa meal that do not come from genetically engineered sources.
Biodynamic manures certified by Demeter USA require that the animals be fed only “USDA Certified Organic” feed, but will be difficult to come by. Seaweed/Kelp and Bat guano products would qualify, but have major sustainability questions about them. Lots of potential with seafood/fish by products, and finally … a personal possible solution.
Many thanks to Emanuel Farrow, a consultant to both conventional and organic farmers, who helped point me in the right direction and provided important fact checking expertise for this post.