Answer: Generally speaking, if the plants are producing well you don't want to rock the boat too hard. Blueberries are not ordinarily given a hard rejuvenation pruning the way some badly overgrown ornamental shrubs are occasionally treated. Instead, regular annual pruning will help maintain the most productive branches while removing older, less productive wood. Overly long branches can also be tipped back. You should be able to reform the bushes gradually over the course of about three years. The following web site
includes a helpful diagram and explanation about blueberry pruning.
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