Jarrod O. Miller, Extension Agronomist, jarrod@udel.edu
Nitrogen (N) can be found in many forms in the soil, some of which can be lost as a gas or through leaching. Some commercial products have been developed to keep N in available forms that are not easily lost until the plant can take them up. These include Agrotain Ultra, Nutrisphere-N, NZone, and Instinct. In a recent study on urea granules, only Agrotain Ultra was successful in slowing the transformation of urea into ammonia, which can be lost as a gas. Both Nutrisphere-N and NZone were not successful.
Nitrification is a process that transforms N into nitrate, a plant available, but easily leached form of N. This same study also observed nitrification with urea, SuperU granules, and urea treated with Nutrisphere-N, NZone, or
Instinct. Of these products, only Super U granules and those treated with Instinct had slower nitrification. Both Nutrisphere-N and NZone were not successful.
The study can be found in the Agronomy Journal and currently has open access to the public: https://dl.sciencesocieties.org/publications/aj/articles/111/3/1441