I have a few shrub roses that have been blooming and wilting immediately. I believe I’ve been over-watering and that will be taken care of. However, it appears there may be more than one culprit. I would very much appreciate it if someone confirm my diagnosis and let me know if there is a separate disease/pest at work besides my unfortunate gardening skills.
I would give all of your rosebushes a treatment of Bayer Tree & Shrub Granules. This product has both a fertilizer and an insecticide/disease control element to it. The fertilizer helps give the rosebushes strength to help fight stresses and shocks and the systemics move up through the root system and into the roses natural juices to get after the insects that like to munch on and skeletonize the leaves. Apply per the label instructions for Shrubs/ornamentals. The blooms may be effected by some thrips as to why they wilt quickly. Water the rosebushes well the night before any insecticide or fungicide treatment. Then water again lightly after the application.