Inorganic Nutrients - A variety of mineral elements (salts) supply the macronutrients and micronutrients required in the life of a plant. Elements required in concentrations greater than 0.5 mmoll-¹ are referred to as macronutrients and those less than 0,05 mmoll-¹ as micronutrients.

When mineral salts are dissolved in water, they undergo dissociation and ionisation. In a medium one type of ion may be contributed by more than one salt. For example, NO³ ions are contributed by NH₄NO₃ and KNO₃ in MS medium and K⁺ ions by KNO₃ and KH₂PO₄