There are 17 elements that are essentials for plant growth. Nurients are divided in to two main groups depending on how much is needed by the plant. Nutrients needed in large amounts are called macronutrients. Nutrients needed in small amounts are called micronutrients. The macro nutrients are subdivided into primary nutrients and secondary nutrients. The primary nutrients are Nitrogen, Phosphorus and Potassium. The second nutrients are Magnesium, Sulfur and Calcium.

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