Q.Single encore azalea ? dying while the rest appear healthy.
Good fall blooming of my encore azaleas, then in late November single plant showed leaves turning scarlet gradually changing to orange, then brown, and shedding. Accelerated death of blooms. So far I cannot identify pests or specific leaf spotting. Process is progressive and plant may be dying. My location is a small barrier island, mid-coastal N. C. Fall has been
mild with probably average rainfall. Plants are mature about 10 yrs. old
and previously healthy. Please share thoughts/ suggestions.
Is this plant in the same area as the rest? if it is not, then I would say that the pH of your soil is thrown off, and can be corrected with a little dolomitic lime. If it is in the same area then I might suggest that it could be a cultivar specific infection, which will require wettable sulfur, and dolomitic lime to correct. These azaleas are quite different than other cultivars, and may require different care.
Alternatively, it may, simply, require some fertilization.
Here is an article that will help you: https://www.gardeningknowhow.com/ornamental/shrubs/azalea/common-azalea-problems.htm