Answer: Rhododendrons do not require much fertilizing. Ideally you would fertilize based on the results of soil testing indicating a need for it. It is better to underfertilize than overfertilize.
With a new plant, I would suggest waiting until next spring to fertilize, then giving it a complete slow release granular fertilizer formulated for acid-loving plants (such as Hollytone) per the label directions.
In the meantime, you could top dress with a good quality compost and be sure to mulch with two to three inches (no deeper) of an organic mulch such as pine bark or pine needles. This will help feed the soil gradually as it breaks down over time, too.
Enjoy your PJM!
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