Answer: Rhododendrons will grow thin and leggy in shade, denser in more sun. Some varieties tend to be naturally denser than others as well. Avoid overfertilizing with nitrogen as this can cause overly long or leggy growth. The best you can do is encourage branching by pinching or pruning out some of the growing tips on the new growth each spring. Each pinch will cause the plant to branch at that point. You can also selectively prune out overly long branches to keep the overall look more compact. I hope this helps.
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