Succulent, sweet blueberries are a welcome addition to the home garden. Proper fertilization helps ensure your blueberry bushes continue to produce healthy berries each year. Most blueberries only require extra nitrogen, but your soil test may indicate otherwise. Blueberries prefer acidic soils, which many home gardens don't provide. Improving the soil quality for the blueberries is helped along with proper fertilization to provide the required acidity as well as maintain it for the life of your blueberry bush.
Test your soil with a pH test kit, following the package instruction. Use the soil acidity percentage as a guide when purchasing fertilizer.
Fertilize as follows if a soil test is not performed; otherwise, adjust numbers to complement the soil test. Apply ammonium sulfate fertilizer four weeks after the initial planting. Apply 1 oz. of fertilizer per plant. Dig the fertilizer into the soil 12 inches from the shrub's base to avoid burning.
For fields of blueberries where no soil test has been conducted, apply 8 lbs. of nitrogen rich fertilizer per acre the second and fourth year before the buds open on the blueberry branches in spring. Apply 15 lbs. the fourth and fifth year, 22 lbs. the sixth and seventh year, and 32 lbs. thereafter. Adjust fertilization amounts as dictated by soil test if applicable.
Apply the fertilizer in a row 12 inches out from the base of the plants on either side. Sprinkle the fertilizer evenly in each row, applying half to each side.
Water the bushes well after applying the fertilizer to speed root absorption of the nitrogen. Avoid splashing the water onto the underside of the leaves.
Things You Will Need
- pH test kit
- Soil tests under a 5.0 pH require fertilizer with 45 percent nitrogen. Over 5.0 pH requires 21-percent nitrogen fertilizer.
- Double the recommended fertilizer amounts if your blueberries are planted in mineral as opposed to organic soil.
- The proper pH range for blueberries is 4.5 to 5.0 percent.
- Do not use fertilizer containing chloride, because it will damage your blueberry plants.
- Fertilizing too close to the trunk of a bush or getting fertilizer on its branches will damage and possibly kill your shrub.