I live on a large property in the South Surrey/White Rock area and have a large amount of Rhodos planted in various exposures. I am noticing recently that the leaves are turning red. I have never experienced this before. The only thing I can find on the internet in ramorum leaf light but the symptoms are not totally compatable. Any ideas anyone?
Sunburn? Did you cut some trees down? Older leaves only turning entirely colorful red could be autumn leaf drop, perhaps triggered early by drought. Or are you talking about (dusty and) reddish blotchy looking? This could be rhododendron mildew, by now ubiquitous down here. Look for the dustiness on the underside, with a lens you can easily see it is actually a moldlike fungus growing over the leaf surface.
I haven't cut down any trees...this doesn't look like sun scald. The leaves start to turn a light green then a blush of orange turning to an orangey-red. The leaves look healthy, no leaf curl & can't see any fungus. I thought it might be drought but some of them get plenty of water with good drainage; they're on a burm. These are juvenile trees, planted maybe 3 years ago, now 3-4' high.
