If you need to lower soil pH, use finely ground sulfur. You'll need to add sulfur to the soil and mix it thoroughly several months before you plant. To lower the pH from 6.5 to 5.5, use about a pound and one-half of sulfur for 100 square feet of soil. Double the amount to 3 pounds to lower the pH from 7.5 to 5.5. You can also use aluminum sulfate to lower soil pH and increase the availability of iron.
Aluminum sulfate is water soluble and can be applied on soil and watered in.
Apply aluminum sulfate at the rate of three ounces for each square yard of soil. On soils of high pH, treat again in two or three months. Contact your Extension Office if you need more specific information about soil pH. Organic matter important For small planting of blue-berries, you can improve the soil structure by adding organic matter. You should use at least one gallon of wet peat moss for each plant. Ideally, soils for blueberries should contain a lot of organic matter.