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| Chemical Fertilizers |
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| These are nutrient supplements for plants manufactured in fertilizer factories from chemicals. They are nutrient specific i.e., they may provide only nitrogen, only phosphorus or only potassium to the soil. They are often used when a particular nutrient is required in the soil for a particular crop. Chemical fertilizers contain a higher amount of nutrients as against manures and so are used in very small quantities. |
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| Based on the availability of nutrients in them chemical fertilizers are divided into four groups: |
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 Nitrogenous fertilisers |
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 Phosphatic fertilisers |
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 Potassic fertilisers |
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 Complex fertilisers |
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| Fertilisers that contain the macronutrient nitrogen come under this group. |
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| Example: Ammonium sulphate, ammonium nitrate, sodium nitrate, urea. |
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| Fertilisers that contain phosphorus come under this group. |
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| Example: Superphosphate, ammonium phosphate, calcium phosphate (bone meal), ammonium hydrogen phosphate |
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| Fertilisers that contain potassium come under this group. |
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| Example: Potassium chloride, potassium sulphate, potassium nitrate |
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| When a fertilizer contains two or more nutrients it is called a complex fertilizer. |
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| Example: Nitrophosphate, ammonium phosphate, and urea ammonium phosphate |
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| Although chemical fertilizers do increase crop yield, their chemicals get washed away through irrigation, rainfall and drainage and reach rivers, lakes and streams. They pollute them and disturb the ecosystem. Therefore chemical fertilizers should not be used indiscriminately. |
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