Wysteria use a rose-type fertilizer. They should only be fed once a year in early march. My roses seem to get a lot of brown spots on the leaves. The roses seem okay the rose bush looks bad. I do feed them.
Roses are susceptible to black-spot disease.
This shows up in the form of black spots on the leaves. Treat the leaves with a good rose fungicide. The American Rose Society suggests 'Funginex'. Apply according to label directions. Roses need monthly feeding during the growing season with a rose-type fertilizer.