There is a foliar spray preparation comonly known in latin america as biol. I have tried to find scientific papers on it, but have only found a few thesis. I want to do a search in english bit dont know how it is called in the anglosphere.
Hoping someone can recognize it, Ill describe how to make it, maybe someone will try it to.
You will need:
. A sealeable 200 l plastic drum.
. An irrigation conection and a rubber seal for it.
. A piece of hose.
. A plastic bottle.
. A piece of wire.
. 50 kg of fresh cow manure.
. 5 l of milk serum
. 5 l of molases.
. 180 l of rain water.
. 2.5 kg of rock flour.
. 2.5 kg of ash.
Drill a hole on the tape and conect the hose using the irrigation conection and rubber seal, it should be airtight. Tie the bottle to the drum and fill it with water.
Mix all the ingedients and stirr. Put the lid on and put the hose inside the bottle so no air can get in but gases can get out (a water seal).
Let it be for 1 to 3 months (depends on climate). If it smells bad like a drain, "bad" microbes colonized it and it will be toxic to plants. It should smell sweet and sour.
We use it in 20 to25% concentration in amaranth and corn.
I seem to have found the term you would use to name the cathegory in which biol would fall in english: organic anaerobically fermented foliar fertilizer.
I´ve done a coagulation trial with it by mixing it 1 to 1 with 97% alcohol and found it to be rich in aminoacids wich is a form of N that helps plants be resistant to some insects, I´ve eliminated aphids in alfalfa using it mixed 4 parts biol and 17 parts rainwater with some molases and humic acids applied 3 days appart (dose needed may change acording to soil and plant health).
As said before you can ad micronutrients during the fermentation process. I am not sure but I belive Mn and Fe need to be in reduced forms in order to be usefull tu plants, this recepi should be very reduced with all the molases and anaerobic environment.
I don´t belive there are many microorganisms alive at the endo of the process, but it should have many microorganism carcasses and therefore it should not leach in the soil and would stimulate microorganism growth in the soil (aerobic microorganism growth too if the soil is well aerated). Maybe it contains viable spores of microorganisms and I´ve heard it contains Baciluss subtilis wich is a beneficial facultative (both aerobic and anaerobic).
Hope someone gives it a try.
I have a knack for fixing things like this ... um ... sorry ... here is a concilitory tiny ad:
100 ways to cut one's personal carbon footprint - in order of tons of carbon