With plants spread out over an acre, that would be an enormous amount of soil testing to be done.
What is fairly clear, though, is that the native soil, at least in this garden, is acidic clay. I have measured it at 5.0 in some places.
More typically it has been in the 5.5 - 6.0 range.
Just to be clear, does inadequate potassium promote rust?
Thanks so much for your help.
