How much peat moss should be used to effectively lower the pH level of the soil?

The amount of peat moss needed to lower the pH level of soil depends on the current pH level and the type of soil. Generally, a good starting point is to mix in 2 to 3 inches of peat moss into the top 6 to 8 inches of soil. It's important to test the pH level regularly and adjust the amount of peat moss as needed.