Soil Acidity and Liming Soil acidity is one of the environmental factors which can influence plant growth and seriously limit crop production. In order to correct soil acidity, ground agricultural limestone should be applied to the soil at rates determined by soil test or diagnostic chart. While the response of crops to lime may not be seen as quickly as their response to fertilizer, failure to use lime limits crop yields. Agricultural lime will also increase the efficiency with which crops use the fertilizer applied. Combating Soil Acidity The quickest way to neutralize soil acidity is by applying agricultural limestone to the soil. A good liming program is based on a professional laboratory soil test that determines the degree of soil acidity and the correct amount of lime to use. Other options include the use of field test kits or a diagnostic chart. How long will it take for the lime to react with soil and how long will it last? It normally takes lime 2 to 3 years to react completely with soil. Apart from the quality of the lime, reaction time will also depend upon amount of soil acidity, soil organic matter, type and amount of clay and the cropping practices. The effect of lime can last up to 3 or 4 years, but this does not mean that it will not be necessary to apply more lime during that period. Not all acidity is neutralized at once, so regular applications of lime may be necessary. Lime should be applied well ahead of planting acid sensitive crop so that there is enough time for the reaction to begin. It is important to note that the chemical reaction of lime in the soil requires moisture. Causes of soil acidity – Soil acidity occurs as a result of:

• Acidic parent material that forms the soil
• High volumes of rainfall and leaching of elements like Ca and Mg
• Decay of organic matter leading to release of organic acids into the soil
• Harvest of high yielding crop which removes plenty of Ca, Mg, and K from the soil
• Widespread use of nitrogen fertilizers