Plant growth can be greatly hampered by soil being too acidic. This is especially important when N fertilizers form acids. As N fertilizers are used to grow more food, soils are continually becoming more acidic. Soils with too much acid can cause several problems. Many forage plants, like alfalfa, have specific soil acidity tolerances (measured as pH) for productive growth, but as acids increase soil pH drops and growth is hampered. Nitrogen fixation is also hampered in very acidic soils. Acid soils have poor tilth and are poorly aggregated. Other nutrients are not as available to plants. The concentration of soluable metals in the soil may become toxic. There may be a calcium deficiency. Lime is used to reduce acids and make the soil more alkaline.


Limestone can be purchased in several forms.


Limestone reacts only with the nearby soil, so mixing the limestone into the soil rather than leaving the limestone on the surface is necessary. Disking alone is not enough and may result in green stripes in plant growth. Disking followed by plowing, and further working in of the limestone is best.



Lime is beneficial when mixed well into the soil where seeds are germinating and plant roots growing. Lime should be placed deep enough to serve these purposes.


Lime applications can be expensive. Some alternatives may provide an inexpensive solution. Since lime encourages nodulation, using more inoculum may be helpful. Apply Mo at 4-5 oz/A, and P. Use species tolerant of acidic soils such as white clover or subterranean clover.