Fertilize lightly and often, using a formula specifically made for blueberry plants. If your plants are mulched, use 1.5 oz. of 12-4-8 fertilizer per plant; if plants are unmulched, use 1 oz. per plant. Fertilizer should be applied in a 2-foot circle underneath the plant. Apply fertilizer in April, June, August and October. In subsequent years, you can increase the amount of fertilizer applied, but also increase the size of the circle under the plant where you apply. For example, increase fertilizer to 2 oz. per plant, but spread over a 3-foot circle.
Water thoroughly and often. Mature blueberry plants require 40 inches of water annually. The most critical watering period is from early fruit set until the harvest; little water is needed over the winter. Most plants are bred for drought-resistance and, once mature, can survive some dry periods.
Prune canes with sharp clippers, cutting at the base of the cane. Pruning stimulates new growth, and new branches are more prolific than older ones. Generally, you should remove one fourth of the old canes each year; this will ensure that all branches are less than 4 years old. Complete pruning should take place during the summer immediately after the harvest. Misty blueberry bushes also require some late winter pruning to remove a portion of the flower buds; this will result in larger fruit.