wisteria branch has a white powdery look on it….how do I care for this problem
How do I take care of my wisteria, which has a white powdery looking growth on some of the branches?
White powdery substance on the leaves is usually 'powdery mildew', but you say on the branches. If you mean on the woody stems it could be lichen, which is not a harmful pathogen.
Powdery mildew can be controlled with 'Green Cure' or another fungicide spray. Although at this time of year it won't be long before dormancy and leaf drop. But you can wait until spring and do preventive spraying with neem oil or the GreenCure for next season.