How to Get the Right pH in Blueberries

If Soil pH is 5.5 to 7

• 1

  Add acid peat to prepare the soil if the texture of the soil is sandy to sandy loam. Mix 4 to 6 inches of acid peat to the first 6 to 8 inches of soil. The acid peat will both acidify the soil as well as increase the organic matter content which blueberries need to thrive.

• 2

  Add elemental sulfur as an alternative to acidify the soil. For sandy soil, use 1 to 2 lbs. of elemental sulfur to 50 cubic feet of soil to achieve one point of pH reduction. You will need to use three times the amount of elemental sulfur for loamy soil. The disadvantage of this method is that you will have to wait at least one year to see the lowering of pH.

• 3

  Add iron sulfate for faster acidification. For results in less than one month, use iron sulfate on blueberry plants. However, this is a more expensive treatment and requires six times the quantity of elemental sulfur.

If Soil pH Is 7 or Higher, or Lower Than pH 4

• 4

  Prepare a raised planting bed. In general, soils with greater than a pH of 7 are not recommended for blueberry cultivation. Greater modification as well as acidification of the soil will be necessary. If the soil is too basic to acidify sufficiently, make a raised bed with the dimensions 15 inches by 24 inches by 48 inches. Fill this with a soil mixture of four bushels of well-rotted sawdust, leaf mold or peat; two bushels of loam soil; and two cups of wettable sulfur. As the soil mixture decomposes over time you will have to test the pH level every year and amend with additional peat, loam and sulfur.

• 5

  Avoid making a raised bed if the soil is dry and sandy. Dig a hole in the ground of the same dimensions as the raised bed and fill with the same soil mixture.

• 6

  Apply dolomitic lime to increase pH to the proper range for blueberries if the soil pH is lower than 4.

Take Into Account Fertilizers' Effect on pH

• 7

  Incorporate ammonium sulfate into your nitrogen-based fertilizer regimen for blueberries. By doing so you will help lower soil pH.

• 8

  Add calcium sulfate instead of limestone for calcium enrichment if pH levels are a concern. Calcium sulfate will not affect pH as greatly as will limestone.

• 9

  Treat blueberry plants with micronutrients if soil pH becomes too high and micronutrients become unavailable. Iron in the form of chelated iron may temporarily lower soil pH.