by Wayne Flanary, regional agronomist
The application timing of ammonia as a nitrogen fertilizer in the fall deserves careful attention. Growers should consider long term research that indicates that soil temperatures should approach 50 degrees Fahrenheit at a 6-inch depth before application.
It is better to even wait till soil temperatures reach 40 degrees Fahrenheit. Once soil temperatures drop below this level, ammonia conversion is slow and risk is reduced.