Answer: Rhododendrons can be pruned back by removing individual stems that are overly long. If you are taking off just a small portion of the bush (say less than ten percent of the overall bulk), you can do it now. (Right after bloom is the best time to do light pruning.) If you need to take them back substantially, a better time would be very early next spring before they bloom. This will remove the flower buds but is less stressful on the plant when you need to cut it back hard. If they are truly too big for their location, you might want to replace them with something that matures to a smaller size. Otherwise you will be pruning regularly every year or hard pruning every few years. I hope this helps.
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