Can we use ferrous sulphate to the maize crop? Will it be useful or harmful? and if applicable how to apply?
Yes you can apply ferrous sulphate to the crop. it is beneficial for applying in calcareous soil.
you can apply through foliar spray and soil application.
for foliar spray the water soluble form will be use and the rate of application is 10g/liters of water.
for soil application apply 5-10kg/acre along with mixing of 100kg fym.