The last few years my Rhododendron only blooms on the bottom half. Any idea why?
Why Does My Rhododendron Only Bloom on the Bottom Half
Certified GKH Gardening Expert
If I had to venture a guess, I would say the top half of your rhododendron suffered frost/winter damage at some point which, given these harsh winters we have been having, really is not too far fetched. I recommend pruning the top branches of your rhododendron once the blooming period is over. More specific information on pruning rhododendrons can be found here: https://www.gardeningknowhow.com/ornamental/shrubs/rhododendron/pruning-rhododendrons.htm
Then, from this point forward, I would take measures to protect your rhododendron in the winter - these measures are discussed in detail in the following article: https://www.gardeningknowhow.com/ornamental/shrubs/rhododendron/rhododendron-winter-care.htm
For more information on the care of rhododendron, please visit the following links: