"Hartz" Ratio Distribution in IN, MI, OH and PA:

The distribution plots are based on soil tests sent to us by tomato growers and collaborators and show the diversity of soil characteristics of this region. Percentage of farms falling in each range are listed above the distribution bars. Soils that are at lower or higher risk are indicated.

The “Hartz” ratio is the amount of exchangeable potassium divided by the square root of the magnesium in meq/100g units.  To estimate the "Hartz" ratio of your soil click here.