Spring Nitrogen Stabilization

Jan 24, 2022

One of the most important decisions in corn crop production is nitrogen applications. Timing and stabilizing nitrogen are two decisions that can have a huge impact on the farm. We see a trend of fall applied nitrogen with a stabilizer and spring applied nitrogen without a stabilizer. The idea here is the fall applied has a longer time to leach away so we stabilize it. This thought process of only longer time is not the correct way to think about stabilizing nitrogen. When applied, Anhydrous Ammonia is in a positive form. It takes soil bacteria to convert this nitrogen into the negative form that can move with water. These bacteria are active in warm moist conditions. We try to apply nitrogen under 50-degree soil temps in the fall because these soil microbes are not very active. We do not see as much nitrogen loss in the fall compared to spring because spring temperatures are warmer and bring more rain. This brings up the question of should we stabilize in the spring?

Our recommendation here at SFG is to stabilize early spring nitrogen applications because we can see just as much loss in the spring compared to fall applications. If it is worth stabilizing in the fall it should be worth stabilizing in the spring as well because that is when nitrogen losses occur. Corn uses most of its nitrogen during the rapid growth phase in June. If nitrogen is applied in April, we still need to keep that nitrogen around for two months. Non stabilized nitrogen at 60 degree temps only takes about two weeks to convert to a mobile form. There are generally many spring rains that can move nitrogen during this time period. A one-inch rain can move mobile nitrogen as much as six inches. Using stabilizer in the spring can help ensure and give us peace of mind that nitrogen will be in the root zone when corn needs it. Reach out to your SFG Agronomist to talk about nitrogen stabilizing options.