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Cereal Facts
• Fertilizers are natural or artificial substances added to soil to make crops and garden plants grow better.
• Natural fertilizers such as manure and compost have been used since the earliest days of farming.
• Manure comes mostly from farm animals, though in some countries human waste is used.
• Manure contains the chemicals nitrogen, phosphorus and potassium plants need for growth. It is also rich in humus, organic matter that helps keep water in the soil.
• Artificial fertilizers are usually liquid or powdered chemicals (or occasionally gas), containing a mix of nitrogen, phosphorus or potassium. They also have traces of sulphur, magnesium and calcium.
• Nitrogen fertilizer, also called nitrate fertilizer, is made from ammonia, which is made from natural gas.
• The first fertilizer factory was set up by Sir John Lawes in Britain in 1843. He made superphosphate by dissolving bones in acid. Phosphates now come from bones or rocks.
• Potassium fertilizers come from potash dug up in mines.
• The use of artificial fertilizers has increased in the last 40 years, especially throughout the developed world.
• Environmentalists worry about the effects of nitrate fertilizers entering water supplies, and the huge amount of energy that is needed to make, transport and apply them.