I’ve used lactic acid ferment to chelate iron and manganese. Individually I was able to get 12kg of sulfate into 200L of lactic acid bacteria. Any more sulfate than this seems to kill of people at least stunt the bacteria. Application rate was 10L her ha to move the numbers on saps.

I’m trialing a citric acid chelate this month to see if I can get the percentage in solution up and the application rate down. I should have sap and liquid sample results next week or so.