Answer: The best time to prune your sweet bay is in the spring, just as new growth appears. Pruning encourages new growth. If you prune in late summer or early fall, new growth won't have a chance to harden off before winter weather arrives, which could result in winter dieback. If possible, wait until spring to do any major pruning. The general rule of thumb to keep shrubs happy and stress-free is to remove no more than one-third of the live growth during any pruning session. This means you can reduce your 15' shrub by about 5'. If you need to take more off, plan on doing it over several years of annual pruning.
Best wishes with your landscape!
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