Soil pH is the measure of the acidity (sourness) or alkalinity (sweetness) of a soil. The pH ranges from 0 To 14. 0 being most acidic and 14 being most alkaline. A pH of 7 is considered neutral.For most plants, the optimum pH range is between 5.5 to 7.0, but some plants will grow in more acid soil or may require a more alkaline level.
The pH is not an indication of fertility, but it does affect the availability of nutrients. Even with adequate nutrients in the soil, the growth of plants may be limited if the pH level is not proper.
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