lueberries require highly acidic soil with a pH between 4.5 and 5.5. Standard potting soils or garden soils are typically neutral to slightly acidic (pH 6.0–7.0) and are not acid enough on their own. To grow blueberries successfully, you will need to mix in acidifying amendments such as peat moss or elemental sulfur, or use a specialized acid-loving plant planting mix.