Rhodo diagnosis? Borer?
First of all - my apologies for having to do this post in successive posts, as I can't figure out how to get all my pictures in on post.
I have had 3 mature (15 - 16 years) rhododendrons that have thrived thru the years. Two years ago one quickly - and seemingly suddenly - died, and I replaced it. This year the other two bloomed as usual, but I noticed the second one was thin, spindly, has lost leaves, etc. since bloom season has passed I've noticed it quickly succumbing to ___?____ . Not only that, the one I planted two years ago looks the same.
I always fertilize with Holly-tone after blooms have spent, and I did so this year. This is when I first noticed the second one not doing well. I've been watching it go downhill since. I did try a light spraying with a fungicide/miticide/insecticide I have for my roses. It didn't seem to make a difference either way.
Been looking up rhodo problems on the internet and wondering if it has a borer. I've cut some top halves of dead branches off and don't see any holes inside the stems.
I'd hate to lose my last healthy one. I already hate losing the one, and almost the second one.
The pictures - coming in successive posts - will show the healthy one and then the two others --- one the new one, the other the mature one.