I just noticed one of my shrubs in the garden has a huge, vertical crack spanning almost the entire length of the plant. This plant has no issues and had a lot of foliage in previous years. Is this some kind of disease or sign of old age and dying? Anything I can do to save or reverse it?
A common cause of bark splitting is freezing in unusually cold weather. It may be killed or not , but it is an entry point for fungus and disease. You could just leave it and take a chance or start looking for a replacement. I do not know any way to significantly help it. I have three large gardenia bushes that have similar splits from the severe February freeze in TX caused by global warming. They appear to be dead while a fourth gardenia was not split is is is putting on some new growth.