Answer: The answer to your question really depends on what kind of shrub you are pruning. Most early spring flowering shrubs such as spirea and forsythia and lilac should be pruned in spring right after they flower. Yews can be trimmed as needed during the growing season as can privet. Avoid pruning in fall as that can stimulate new growth which will not have time to harden off before the cold winter weather. If you have a specific shrub in mind you might try searching the Q&A for specific pruning instructions.
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