Click on a thumbnail picture below to see the full size version. 1 Entries. Friday, March 24 View Page 2017 Soil Test. Phosphorus has always been very high. Manganese has always been very low. Some university extensions say not to add manganese if pH is over 6.5 or if OM is very high, as it will quickly be converted to a fixed/unusable form. Would it be better to to just do foliar applications of manganese? Other advice?