Which of the following statements about lime and soil pH is true?

Which of the following statements about lime and soil pH is true?

• A. Lime raises pH
• B. Lime lowers pH
• C. Lime has no effect on pH
• D. Lime acidifies soil

Answer: (A)

Lime raises soil pH by neutralizing soil acidity. Soil pH reflects how acidic or basic the soil solution is, and many soils become acidic from rainfall, crop nutrient uptake, and organic matter breakdown. Lime, often calcium carbonate, is alkaline and dissolves in soil water to release calcium ions and carbonate. The carbonate neutralizes hydrogen ions in the soil solution (and can also reduce exchangeable aluminum toxicity), effectively lowering the acidity and increasing pH. In short, adding lime makes the soil less acidic, which is why it’s used to raise pH.

Lime raises soil pH by neutralizing soil acidity. Soil pH reflects how acidic or basic the soil solution is, and many soils become acidic from rainfall, crop nutrient uptake, and organic matter breakdown. Lime, often calcium carbonate, is alkaline and dissolves in soil water to release calcium ions and carbonate. The carbonate neutralizes hydrogen ions in the soil solution (and can also reduce exchangeable aluminum toxicity), effectively lowering the acidity and increasing pH. In short, adding lime makes the soil less acidic, which is why it’s used to raise pH.