The pH for Fertilizer for Blueberries

Types

• Select and plant the proper type of blueberry for the region where it will grow. The northern region of the country calls for the lowbush varieties, Vaccinium angustifolium, including Polaris and North Blue. Highbush varieties V. corymbosium do well in the mid- section of the country and include Blue Moon and Jersey. In the South, rabbiteye, Vaccinum virgatum Syn. V. asher is the blueberry of choice with Woodard and Brightwell among the most widely grown cultivars.

Required pH

• Both lowbush and highbush varieties of blueberries prefer a soil pH between 4.5 and 5.5. The Southern rabbiteye blueberry prefers a pH between 5.5 and 6.0. The only way to know the pH of the soil is to have the soil analyzed for pH, phosphorous and potassium. Soil with pH higher than 5.1 can be amended with an application of sulfur or aluminum sulfate. A high pH will cause the berries to turn yellow as they are unable to absorb iron. A low soil pH, under 4.0 can be raised with the addition of dolomite lime to the soil.

Commerical Fertilizer

• Nitrogen is the most important and often the only element blueberries require. Apply nitrogen in early spring in the form of ammonium sulfate or sulfur coated urea, which helps lower pH. Do not apply fertilizer that contains nitrates, such as calcium nitrate or chloride, as some blueberries can be killed by nitrates. Commercial fertilizer specifically formulated for blueberries and the region in which they are planted are often available at local garden centers.

Organic fertilizer

• Soil for planting blueberries can also be amended organically by using blood meal or fish meal for nitrogen; and sphagnum peat or coffee grounds for acidity. Bone meal or powdered seaweed provides potassium and phosphorous to the soil.

Application

• Apply fertilizer a month after planting being careful to avoid getting fertilizer on the stems. On older plantings apply fertilizer in early spring before foilage is present. Apply the fertilizer by hand or broadcast by applicator evenly around the base of the plant. Avoid having fertilizer touch the foilage as it will damage the plants.