Why do plants grow better if lime is added to the soil?
Calcium frees other nutrient metal ions from the soil and makes them available for the plants. Plants need potassium and magnesium to grow. But these metal ions have positive charges and they are locked onto clay particles in the soil which have negative charges. If lime is added, the calcium ions then stick to the clay particles, and the metal ions, which the plants need, are released. Why do some plants not grow well if there is too much lime? The mechanisms that certain plants have for growing in acid conditions backfire when lime is added. If the soil is very, very acid, then aluminium and iron compounds will dissolve. Aluminium ions are toxic to plants. (That is why acid rain is a problem). Just a few plants have methods of preventing the toxic aluminium from entering. These same methods also prevent iron from entering. If lime is added then iron as well as aluminium become more insoluble. So the plant cannot get enough iron. Habitats The variety of plants in Langcliffe Parish is
