Answer: As with many of the larger spring flowering shrubs, this one does better with an occasional renewal pruning to try to keep it growing vigorously. You might consider cutting it off at the ground to rejuvenate it by forcing new growth. This type of drastic treatment should be done about every five years or so -- when you see it going into decline. Alternatively, you can remove some of the oldest stems each year so that the shrub is always sending out new growth. You would also remove any dead wood annually. Another possibility is that voles have attacked the roots or some other problem is occurring, but unless you find anything unusual, I would suspect it simply needs to be renewed.
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