are substances added to the soil sprayed on leaves of plants to help them grow better or in some cases faster. Plants need twenty essentail elements to help them grow. Plants make carbohydrates. A plant needs nitrogen, phosphorus, potassium, calcium, sulfur, and magnesium the most to grow healthy. Most soils naturally contain enough trace elements for field crops, but such elements must be added when certain fruits and vegetable plants are grown. Nitrogen, phosphorus, and potassium are the top three elements needed in plant growth. Legu ....