Magnesium is a vital nutrient for the development of plants, since It constitutes the central core of the chlorophyll molecule, it is actively involved in photosynthesis and helps activate many enzyme systems. As a result, magnesium deficiency in plants can lead to hampered growth and poor crop results. To counteract this, Magnesium Oxide is preferably used as a fertilizer by itself or in formulation with others due to its high concentration in Magnesium.

More specifically, Magnesium can help in the stabilizing the ammonium nitrate prills, where the Mg-source (MgO or MgCO3) reacts with nitric acid to produce magnesium nitrate. The latter is in turn incorporated at low amounts in the ammonium nitrate product to protect its structural integrity. Another important application is the use of MgO powders in NPK type fertilizers to either increase the Mg nutritional value or to neutralize excess acidity in the production process.

Magnesium is a vital nutriënt for many crops and is often applied as magnesium hydroxide in foliar applications. Foliar fertilisers are used for targeted input at key growth stages. By spraying directly onto the crop, nutrient availability can be controlled and soil interaction avoided.