Mature blueberry bushes require little pruning. Most blueberry trimming focuses on maintaining a healthy and productive plant by increasing air circulation and light (which fight disease) and removing old and nonproductive shoots or canes. Blueberries that aren't trimmed annually bear less fruit, so careful trimming increases your blueberry harvest. Prune blueberry bushes at the end of the dormant period, once frost danger has passed for your region and before the bush starts growing again.
Check your blueberry bush for dead or damaged canes. Damaged canes are discolored, scarred or bear physical wounds, while dead canes will be tan and brittle.
Cut off the dead or diseased canes at their base using anvil pruners. In between each cut, spray your pruners with disinfectant to avoid spreading disease. Once you've remove all dead or diseased canes, cut off neighboring canes that touched the unhealthy growth.
Prune away any dead twigs by snipping them off the branch. Also cut off branches that cross other branches.
Select two or three old canes to remove from mature bushes. Ohio State University suggests targeting canes 7 years or older first. If your bush is younger than that, remove canes from crowded areas of the bush to increase light and air circulation or skip this step and wait for the bush to mature before pruning out old canes.