More Iowa corn acres could be fertilized profitably with phosphorus and potassium. Both hill (row) and broadcast application have their place. Here's what research tells us about methods of application.
Dumenil, Lloyd; Pesek, John; Webb, J. R.; and Hanway, J. J.
"P and K Fertilizers for Corn - How to Apply,"
Iowa Farm Science: Vol. 19
, Article 5.
Available at: https://lib.dr.iastate.edu/farmscience/vol19/iss10/5