The present invention relates to a crop nutrition composition in the form of water dispersible granules comprising a homogeneous mixture of one or more of water insoluble Magnesium salt, complex or derivative thereof in the range of 1-80% w/w of the total composition and one or more of water insoluble Zinc salt, complex or derivative thereof in the range of 1-50% w/w of the total composition and one or more of water insoluble Iron salt, complex or derivative thereof in the range of 1-50% w/w of the total composition with at least one agrochemically acceptable excipient in the range of 0.01-97% w/w of the total composition; wherein the granules of the composition are in the size range of 0.05mm - 4.0mm and comprises of particles in the size range of 0.1micron-20 microns. The present invention further relates to a method of treating plants and meeting their nutritional requirement by making essential nutrients like Magnesium, Zinc and Iron available to them and also unlocking other micronutrients and trace elements present in the soil which hitherto were not available because of various factors primarily being soil degradation on account of excessive use of synthetic fertilizers. The present invention also relates to strengthening the plants so as to withstand pest infestation. The present invention also relates to a method of biofortification of plant with essential micronutrients.