Fertilizers 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, …showed first 75 words of 589 total…

…showed last 75 words of 589 total…States of America produce at least one billion tons of manure. A small percentage of this manure is spread on fields, but a major portion is dried, ground, and sold for use in small gardens. Another organic fertilizer is guano. Guano is the waste of either birds or bats. Sludge is a fertilizer which comes from the sewage system disposals. Other fertlizers are either found from the waste at meat-packing factories and/or uneatable fish.