We have two Redbud trees and every year after about a month into its growth cycle the new leaves start turning black and shrivel. This then starts effecting the more mature but still young leaves. It does not seem to affect the older established leaves. It does stunt the growth because of killing the new growth. I can spray a fungicide on the trees and it will keep it from getting this but if I don’t spray them later in the year, the same thing happens? I have tried to research it but can’t seem to find an answer to what is or how to permanently stopping it?
The Gardener’s Answer
Hi, Robert: Eastern Redbud (Cercis canadensis) trees are susceptible to several different fungal diseases. This is especially true for Redbuds that are grown in heavy clay, poorly drained soils. Botryosphaeria Canker is the most prevalent and the most destructive. Have you noticed any sunken, dark areas on the branches or the trunk? From the die back that you have described, this may be a possibility. Verticillium wilt and leaf spot are also issues that can cause damage. Treatment is not the same for every disease so before treating any insect or disease problem it is always best to have a positive diagnosis and then a treatment plan can be advised. I just spoke with the Jessamine County Cooperative Extension Service and they are still able to take plant samples for diagnosis. They have provided an outdoor drop off box for your sample and they will take it from there. The Jessamine county offices are located at 95 Park Dr. in Nicholasville. They can be reached at (859) 885-4811. I hope this is helpful.
Kentucky Living-Ask the Gardener