I have 2 Wisterias growing up through an old dead tree. One of the plants is very healthy with lots of new growth, the other one is also growing well but the leaves are brown and yellowing. Both plants are about 2 years old and are treated the same. Any advice would be much appreciated.
Certified GKH Gardening Expert
I would say something is getting the roots. If you can, check them. There are several things it could be from root rot to pests to rodents. It may also be a fungus. As a precaution, treat the plant with a fungicide. I would also check for crown or root galls. It sounds like something is choking the plant and galls would do that. Here is some information that may be helpful: https://www.gardeningknowhow.com/plant-problems/disease/how-to-fix-crown-gall.htm