How to Test For Soil PH

This is a measure of the hydrogen and hydroxyl ion concentration in the soil. The acidity of the soil while the hydroxyl ion concentration is also known as the alkalinity of the soil. This is a chemical factor.

The methods are:

1. Use of litmus papers: the moistened red litmus paper turns blue in alkaline state while the moistened blue litmus paper turns red in acidic state.

2. The use of BDH universal soil indicator.

3. Field testing using printed colour standards.

4. Use of universal indicator paper.

5. Determination of soil PH colourimetrically.

6. The use of electrometric method.

PH Scale

This is a scale which is graduated from 0 to 14 and developed to measure both the hydrogen ion concentration and the hydroxyl ion concentration.

The PH scale can be analyzed as below

PH 2 = strongly acidic

PH 6 = slightly or weakly acidic

PH 7 = neutral

PH 8 = slightly alkaline or weakly alkaline

PH 13 = strongly alkaline

PH 5.5 = PH 7.5 = best PH for plant and soil organisms