New to Rhododendrons and have read conflicting advice as to whether to not to deadhead the spent blooms. As the picture shows these are just starting to bloom.
My belief is it is personal preferance. With large rhododendron it can be difficult but I'm never a fan of leaving dead branches on any plants. Good luck
Like you, I have encountered conflicting advice about deadheading rhododendrons. My personal preference is based on my experience with over 100 rhododendrons on my property, several of them quite large (15 ft). I don't deadhead most of them because there aren't enough hours in the day and, in general, I haven't found that it makes any discernible difference. There are a couple of exceptions though: On some varieties of rhododendrons, the base of the dead blooms becomes very tough (woody) and begins to impact the growth habit of the plant. The plant starts to look quite sparse and generally unhappy. In those cases, removing the remnants of the dead blooms seems to make a world of difference. The only other exception I make is that I remove dead blooms in cases where the dead blooms become really dark and ugly because they detract from the overall appearance of the shrub (but that's just a personal preference thing, it doesn't seem to make any difference to the next bloom).
It takes energy to produce flowers and it takes energy to produce seed pods. Since there is no way to compare an individual shrub with itself, we cannot know with certainty if a plant not dead headed looks better or worse than if it had been relieved of spent flowers, in time to prevent pod enlargement and maturity. However, general indications have been seen that heavy crops of seeds affect subsequent flowerings in a sequence, resulting in behavior like alternate bearing of fruit trees - if specimens otherwise making many pods in a given year are not prevented from doing so with dead heading. Some kinds can develop whole sections dominated by spent pods instead of a solid presentation of foliage (and flowers).
