Spraying will not bring leaves back. In my experience, once they drop from the bottom, they don't come back. You may get some new canes popping up, but usually the new growth is on the top.

If it were earlier in the season, I would experiment with cutting to the ground one or two old canes (depending on how many or few canes are presently there) and feeding with Rose Tone. Usually that provokes my roses to grow a brand new cane or two--with all the usual leaves. This is not a quick fix, however--and given your northern zone, I'm not sure it is advisable to try that this late in your season. Perhaps reserve for next year.

Kate

Hey everybody, it's only the first of august with another 6 weeks of summer, then fall which is usually quite warm at the beginning even here in zone 5.
Mary Lu has at least two months of growing season left and possibly more.
I wouldn't hesitate to cut them back to get new growth.
Consider getting disease resistant shrub roses that don't require much spraying. Of my 400 roses, just a very few have lost their leaves to blackspot. Most, including my climbers, have leaves all the way to the ground. I have similar weather as Mary Lu and don't spray, ever.
Our roses die back severely each winter anyway. Not pruning to avoid new growth this early misses a lot of fall flowers. I prune into late August.

Thanks for the input everyone!

buford...that's what I thought. As I have not had BS this bad before, I wasn't sure if the existing canes would regrow new leaves where the ones had fallen off.

dublinbay, the bushes most affected have always been pretty good in past years. Explorer rose Champlain and a Parkland rose Morden Belle. I use MMM, would that be basicly the same as Rose Tone?

Karl, thanks for your vote of confidence. I am thinking the same. We usually don't have a killing frost here until sometime in November. But this year is anyone's guess what with all the crazy weather we're having. Heat index yesterday was 103 and 101 today. Temps are not all that high but the humidity is a killer.

If I do decided to cut back the bushes this weekend, would you cut all canes back, or just some? How far should I cut back? Morden bell has very long canes that sort of bow down, almost as if they were pegged. (I think this helped hold to moisture/humidity in and escalated the problem.)

I'd cut them back evenly. Remember, new leaves will only grow on new canes that grow from the old or from basal breaks from the base of the bush. Any cane below a new cane will remain bare. The more cane you leave the more bare cane will remain after new growth begins. Consider cutting them back to 6-8 inches, a foot at the most.

Karl, after reading your reply and giving it more thought, this weekend they get severly cut back. In some ways I hate to do it....but they sure look horrible now anyway. As you say, come spring we have to prune back lots of winter kill anyway. By pruning back to 6-8 inches I will be able to get in and clean up all the dead leaves under the bushes and spread some fresh mulch too. I think that would also help.

Should I also apply a feeding of MMM when I prune? I haven't fed these roses since spring. I do think it would help in promoting new basal growth.

Hi Mary, as usual Karl has excellent advice to offer us. Several summers ago the deer came in and 'pruned' my roses extensively. They bounced back and bloomed nicely that fall. I did give them an extra dose of fertilizer and made sure they were well watered to help them over their trauma (actually, I was more traumatized than the roses were!)