pH is simply a measure of how acid or alkaline soil is.
As rain water saturates the soil minerals in the
soil dissolve creating a solution of minerals and
water that the roots absorb into the plane.
The pH of the soil influences how easily a mineral
can be dissolved out of the soil into rain water.
The chart to the
left shows how the availability of each of the most
important minerals are affected by the soil pH.
Most plants grow best in slightly acidic soil because
they have access to all important nutrients that pH.