Application timing can maximize the efficiency of available nitrogen as well as reduce the loss window, which increases profit and safety.
Nitrogen application timing is critically important for crop uptake; it is also the determining factor for the length of time nitrogen is exposed to the environment and the key nitrogen loss areas of denitrification, leaching and surface volatilization.1
Ideal timing for nitrogen application for corn is six to ten weeks after planting, since this is when the crop’s use of nitrogen is at its highest.1 However, nitrogen application during the peak crop demand period may not be possible. Soil texture, drainage, rainfall and/or irrigation are key factors in determining the effectiveness of application timing. Other timing options can include spring pre-plant, side-dress and delayed applications made after planting. Delayed and/or side-dress applications also come with a caveat: Since they are typically used outside of the peak crop demand period they also pose the greatest risk for denitrification, leaching and surface volatilization.