pH 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.

For processing tomatoes it is recommended to
maintain soil pH between 6.5-6.8 (2003 Ohio Vegetable Production Guide -
Bulletin 672-03). At pH below 6.0 the
availability of K, Ca and Mg to the plant is reduced. Liming to achieve a pH
above 6.8 can lead to a cation imbalance and ultimately affect the levels of K
in the soil solution. At alkaline pH (above 7.0) the fixation of K tends to
increase, affecting the amount of K readily available to the plant.