sudden dieback: what could cause it?

ataraxiaSeptember 2, 2013

I moved into a new house a month ago, with three seemingly healthy and well-established rhododendrons in the garden. Suddenly they seem to be dying back. The one in the photo, which is the worst, looked fine less than a week ago.

I would really appreciate any advice you might have, because I don't know what to make of it.

The dieback is on multiple branches, and I don't see any evidence of pests. There is a shallow layer of bark mulch, but it's not right up against the plants. There is also a flowering dogwood in this garden, and it has what I would guess is powdery mildew, but now I wonder if the two issues could be related.

Thank you for reporting this comment. Undo

The two most common causes of sudden dieback are both fungal infections. Various strains of phytophthora cause root rot. This disease is more common in pots, but overwatering, high soil temperatures and poor drainage can lead to it in the landscape as well.

Botryosphaeria effects branches and stems and can appear suddenly - often as a result of droughty conditions. This is probably more common than phytophthora in the landscape.

Unfortunately, there are really no good treatment options once an infection has appeared. Pruning back to healthy green wood, cleaning up and disposing of any fallen leaves, and making sure growing conditions are the best you can provide are the best things you can do.

There's more good information available at rhodyman's website.

    Bookmark   September 3, 2013 at 5:18AM
Sign Up to comment
More Discussions
Please help me identify this azalea
When I purchase my house, it had a beautiful azalea...
Double flower buds
Hi, I have both Haaga and Helsinki rhododendrons. They...
azalea few yellow leaves
I'm having a problem with some of my azaleas. Their...
Largest Indica Azaleas?
I'm thinking of using azaleas as a "living fence"...
Please help to ID those two Rhodos
I found two interesting Rhodos (one elepidote, one...
People viewed this after searching for:
© 2015 Houzz Inc. Houzz® The new way to design your home™