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["Donna &/or Kieran" <holycow@cookeville.com>]

Dolomite at a 2:1 Ca:Mg ratio is good if you have a Mg deficiency, but bad if you have too low a Ca:Mg deficiency already.  The ratio should be about 6:1 for porous soils, 7:1 for clay soils.  The Ca pushes soil particles apart, good for clay, the Mg pulls them together, bad for clay.  But as porous soils lose water too quickly, higher Mg is good.  However, if the ratio goes too far away from these ideal numbers, you may see Ca or Mg deficiency symptoms.  I know a guy in Carthage TN, where presumably only the Carthage dolomite lime has ever been used.  He got a lot of blossom end rot on tomatoes, then one year he put down Ca phosphate and they were suddenly better.  He'd improved the Ca:Mg ratio.    Donna