1. Plants require inorganic materials for the synthesis of food.
2. These elements are obtained by plants in the form of minerals mainly form soil.
3. Chemical analysis of plant ash reveals that about 40 different minerals are needed by plants which are taken from surroundings, (air, soil and water)
4. These minerals are absorbed in dissolved form, i.e. ionic form through root system mainly root hairs.
5. Some minerals are required in large amounts (major) while some are needed only in traces or small amounts (minor).