Understanding Soil pH

Soil pH is a measure of acidity and alkalinity.  The nature pH of soil depends on the material from which it was developed.  Scottish soils range from about pH 4 (very acid), when most crops fail, to about pH 8 for soils naturally rich in calcium or magnesium.

Soils will naturally tend to acidify due to natural processes (e.g. rainfall, crop growth and leaching in drainage water) and some farming practices (e.g. use of some nitrogen fertilsers). Acidifying processes can cause soil pH to fall quite quickly, particularly in sandy soils, and regular pH checks every 4-5 years are required.

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