PPDL Picture of the Week
July 19, 2021
Symptoms Associated With Low Soil pH in Corn
Bob Nielsen, Purdue Agronomy
Low soil pH not only stunts corn growth and development, but can actually
kill corn plants in extreme situations. Besides stunted plants, symptoms of
low soil pH commonly include a beaded reddish or necrotic striping of the
lowermost leaves (sometimes also associated with magnesium deficiency) and
brown stubby (thickened) roots. The soil pH from soil samples taken in the
area of the field depicted in the accompanying images turned out to be 3.9,
which would definitely be classified in the toxic category for corn.
Desirable soil pH values for optimum corn growth are in the mid 6's.