Hi! I have given my Rodadendron some sequestered iron a couple of times this year, and some vine weed killer. At separate times of course. But, it is still showing yellowing branches and leaves under the cover of other normal leaves. We are now in early September, and there is a light chill in the mornings. The last time I gave it some sequester iron was about 6 weeks ago. Should I give some more or leave it alone now as it approaches it dormant period?
Certified GKH Gardening Expert
I wouldn't advise giving it much in the way of nutrients as it approaches dormancy. It also sounds like a pH issue is showing itself. dolomitic lime acts as a buffer, along with giving it a boost of calcium and magnesium. I would put some of this on it. Here is another article that will help: https://www.gardeningknowhow.com/ornamental/shrubs/rhododendron/how-to-fertilize-rhododendrons.htm