Whatever else you do, please quickly remove all the leaves with the fungus on them. The spores otherwise drop to the ground and then splash up when you water. I live in a cool moist coastal foggy climate and rust is a problem yearround here. The best defense is no rust spores on the ground, and you will generally find the infection moves up the plant. So you may have to remove all the leave below the first one where you find it -- that is fine, the rose will be okay. In fact, I have completely stripped plants in my mother's yard (where she had no idea what was going on til the whole plant was covered), and they came back just fine too. It also helps to have fewer lower leaves -- take the bottommost leaves off your plant if they are within a few inches of the ground -- it helps prevent the splash up mechanism. In Florida that is why they use such long grafts on Fortuniana and other plants in that region -- to prevent the transfer of pathogens from ground to plant. This has been a particularly bad year for rust for me, btw. I spray with everything alot, and I still have some. So just stay vigilant. Good Luck, Kathy

K2laser, I live in South Carolina and we have the hot humid summers, not as long as you, but we sure get hot during the summer and the humidity is so thick you can hardly breathe. There are some hybrid teas that are very black spot resistant, I would research that onine and ask in this forum for some names of some of them. You really can't ever get rid of black spot on a rose. You can spray all kinds of expensive sprays dilligently on the rose bush and canes, constantly keep the rose bush real clean, don't let the infected leaves blow into other roses, and they will always have it. I bought for the first time this spring a knock out rose, double red. It is the only rose in my garden that doesn't have black spot. It is absolutley gorgeous! Clean foliage, and grows fast. When I get tired of all the nonsense for my hybrid tea rose trees and black spot, I will buy another knock out. All you ahve to do is water them, don't even dead head them. Low maintance, it is a beautiful thing.

Do you know what type of bushes they are? If there is a way for you to post pictures, please do. That would be very helpful. If you can't do that, give us a description of the shrub...size, color, flower description, is it in sun or shade, etc. Kim Here is a link that might be useful: Kim's Garden

I found a Youtube video of a very similar slime mold growing on an oak tree. I can't attach it with my Kindle fire, but it should be easy to find...'.black slime mold on oak branch '. Okay....now at a different computer. See if this video somewhat resembles what you see on your butterfly bush. Here is a link that might be useful: Black slime mold video This post was edited by rhizo_1 on Mon, Jun 10, 13 at 12:50