I've recently planted two Goldflame Honeysuckle to act as a hedge on my patio. They are now in their third growing season and are staring to fill in nicely. One of the plants has been plagued each season with mildew often causing leaves and flowers to die off. I have been treating with a multi purpose fungicide and trying to remove any affected foliage as soon as possible. Both plants are getting plenty of sun and lots of airflow as they are on a standalone trellis in open air. Any other suggestions on how to keep my plants healthy?

1 tsp. of baking soda per quart of water is a very effective treatment for powdery mildew.
I only suggest it because some of these broad spectrum fungicides can cause a lot more serious damage then the mildew.