Rhododendron - possible dead top two-thirds

Asked April 27, 2015, 8:39 PM EDT

The early, extreme freeze we had last fall didn't help our rhody at all. It was here when we moved to the house 25 years ago, and this is the first time it's had a problem like this. The place it's in is fairly protected from wind and heat. After the freeze, most of the leaves drooped. Now, half or so are gone from the upper 2/3 of the plant and those that remain don't look too good. The buds also look dead. The bottom 1/3 of the plant looks generally OK. Questions: If the stems haven't been killed, will it leaf out? If the answer is a no, then I suppose it best to trim it back to live material and let it grow up again? Suggestions? I've attached a pic. Thanks

Oregon trees and shrubs pruning diagnosis of plant problems

4 Responses

Sorry your picture didn't come through. Can you try again?

Sorry, Sandy. Here, try this again.

Why is your Rhododendron losing leaves and has branch die-back?

If your Rhodie is 25 years old it's unlikely that a short freeze would affect it this way.

Has anything changed? Have you disturbed the roots recently? Have you cut down a tree or shrub nearby that was giving shade? Have you applied any herbicides?

If nothing has changed with your Rhododendron then it may be Phytophthora Blight and Dieback. Phytophthora is a fungus that usually affects the roots but can sometimes affect the leaves and branches depending on what time of year it has come into contact with the plant. The triangular pink/brown patches on the leaves in the photo are typical of Phytophthora.

The page from the Pacific Northwest Disease Management Handbook that I link to above suggests a range of cultural controls including pruning off dead leaves and branches and clearing all debris from under the plant.

There is a also a list of suitable chemical controls too if you choose to go down that route.

Thanks for your interesting question.






That is very interesting that this would be coincident with the hard freeze we had, but it sure looks like the fungal infection is the answer, especially so since only a portion of each leaf is affected. I'll do what I can with it, and maybe the plant will grow back up. Thank you for your help.