The need for fertiliser

• In order to meet the growing population's demand for food, farmers are often forced to produce as much food as possible in the shortest time period.
• The same crops are planted on the same piece of and year after year, without allowing the land to lie fallow (rest) for a few years in between planting periods.
• When a piece of land lies fallow, it is ploughed, but not tilled or planted for one or more seasons
• The lack of fallow period causes the depletion of nutrients and increases the need for more fertilisers
• The use of fertiliser can increase crop yields and also improve the quality of crops
• Fertiliser is any organic or inorganic material that is added to the soil to provide nutrients that are essential for plant growth and development
• Excessive use of fertilisers causes minerals such as nitrogen, potassium and phosphorus to accumulate in rivers and lakes after heavy rains.
• Large amounts of minerals in the water cause algal bloom and consequently eutrophication
• Excessive use of fertilisers can also have an effect on the pH of the soil which adversely affects crop production.
• A more environmentally friendly approach is to practise crop rotation or to use compost to supplement soil nutrients.