How much lime is enough?
Soil test measurements of pH and exchangeable acidity indicate whether enough lime has been applied. The purpose of applying lime is to reduce exchangeable aluminum (acidity) to levels that are not toxic to plants. Research shows that nontoxic levels occur at pH values above 5.5. A soil pH of 6.0 is usually recommended to allow for variation in lime application, soil type, climate, fertilizer effects and crop tolerance. Some crops have a higher target pH of 6.0 to 6.5.
