Dry fertilizers can safely and quickly be applied to a field in the fall. Soil Fertility Specialist Fabian Fernandez says University of Illinois studies have concluded the method of application doesn't really matter much.
"It doesn't really matter if you apply it on the surface leaving it there, incorporating tillage or doing sub-surface banding," Fernandez said. "All the research that we have done shows that there is really no difference in terms of corn and soybean performance on the method used to apply fertilizer as long as you have adequate fertility."
The University of Illinois recommends soil testing every four years in order to better understand and maintain soil fertility. As to the fall P and K fertilizer applications, Fernandez says these can be made every year or even every other year as long as the application is timed with the crop rotation.
As a rule of thumb always try to make the dry fertilizer application prior to a corn crop. And while fall is a good time to make the application, Fernandez says data from the University of Illinois suggest it doesn't matter if the dry fertilizer is applied in the fall or even in the spring as long as it is in place prior to planting. Fernandez does note that those farmers planting corn after corn rather than a corn-soybean rotation should adjust the phosphorous application rate upward.