Acidic soil has a pH of less that 7.0. There are gradations of acidity below 7.0. Soil with a pH of 7.0 to 6.0 is considered mildly acidic. Moderately acidic soils have a pH between 6.0 and 5.0, while highly acidic soils have a pH below 5.0.
Acidic soil restricts plants' ability to absorb nitrogen, phosphorus and potassium. Areas with heavy rainfall often have acidic soils. Soil acidity can be reduced by applying lime to the soil.
The opposite of acidic is alkaline.
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