Answer: It would help to know the variety of rhododendron you are growing. There are a few, such as Rhododendron x ?Milestone', and Rhododendron thomsonii subsp. thomsonii that naturally bloom in December. There's nothing you can do to change the blooming habit - spring flowering is not in its genetic make up and it simply won't cooperate no matter how you try to manipulate the flower buds. If you want spring flowers, you may have to replace your rhodie with one that blooms in May.
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