Fertilizer is any substance that can be added to the sail  provide chemical elements essential for Plant Nutrition, Natural substances such as animal droppings and straw haves been used as fertilizers for thousand of years, and lime has red used since the Romans introduced it during the , It was not until the 19th century, in tact, the chemical fertilizers become popular. Today both Natural and synthetic fertilizers are available in a variety of forms. complete fertilizer is usually marked With a formula consisting of three numbers, such as  Which is designate the percentage content of nitrogen, phosphoric acid, and potash in the order stated. Synthetic fertilizers are in either solid or liquid form. Solids. in the shape of chemical granules are popular because they are easy to ore and apply. Recently, liquids have shown an increase in popularity, accounting for about 20 percent of the “nitrogen fertilizer used throughout the world. Formerly, powders were also used, but these were found to be less convenient ft either solids or liquids. Appropriate uses of fertilizer ray no harmful effects on the soil, the crop, or the consumer. However, excessive uses of fertilizer not only damage crop but also the animals or humans.