Q.rose of sharon
Can I cut my rose of sharon way back ( August zone 5) due to rust fungus?

You certainly can trim it back to shape it and try to get rid of some of the rust fungus. However, if not sprayed it will likey just come back on you to the better foliage you have pruned back to. I recommend spraying the bush down well with a product called Green Cure.It is a fungicide that works very well to get rid of such funguses. It is available to purchase on-line and at some garden centers locally. Mix it at the Cure Rate, which is two of the large scoops that come in the container to a gallon of water in your pump up sprayer. Do this application at least twice about 5 to 7 days apart. Three times even better. Then prune the bush back and spray one more time. things should be looking better then. Link: http://www.greencure.net .