Originally Posted by I wood
Similar deficiencies plagued me while transitioning to recycled soil. After reading slownickel(I think) go on about the importance of calcium in several long and detailed posts I started topdressing with gypsum. Things started getting better quick. I now add a spoonful when remixing soil and top dress at transplant as well.
If I recall correctly, calcium plays a role in the absorption and transport of many other key things.
It is cheap and easy to get, worth a try in my opinion.
I think I Wood is onto something with the gypsum, it'd be worth you running a trial. Back in the ROLS thread Coot and them all would rag on folks running dolo lime, and all the fellows dealing with Cal-Mag lockout issues. At one point he mentioned that this situation is incredibly common in folks running in coco setups because coir is incredibly deficient in sulfur. The sulfur is used by the soil microbiological community to break the carbonate bonds on both Calcium carbonate and Magnesium carbonate, making both Ca and Mg available. Without the sulfur, as sulphate, playing this role you can get these lockout issues. It may be good to try and top dress with some gypsum and see if that helps.
Switching your overall lime mix to something like 1 part dolo:1 parts ag lime:1 part gypsum, and then using 1 cup of this/cf of your soil may help. This would be 26%Ca, 4%Mg, 5%SO4, with a Ca:Mg ration of 7:1, which is aight. The 2:1 ratio of the straight dolomite lime is quite a bit off from what you want, being about 22%Ca, 11%Mg.