I did this same thing just last month. We had an early spring here in the south and my roses had leafed out and bloomed early. I had a horrible outbreak of sawflies and my rose leaves were looking horrible. I cut them all the way back and removed all the foliage. I gave them a healthy dose of greensand and started a weekly neem oil spray regime. I also started an organic foliar fertilizer which has made the leaves super green and healthy. They have come back in full force and look extremely healthy and so far have been fungus and insect free. They will be in bloom again this week and I can't wait! I say go for it. Just be sure to be diligent with whichever spray routine you are comfortable with.

I would not do a heavy pruning like that after the first bloom cycle is over. Seems kinda hard on the rose, plus it needs the energy manufactured by even damaged leaves.

There is no rule that roses MUST be pruned every year. I usually have to prune my hybrid teas hard in early spring because the winters are cold enough that the top half (or more) of the hybrid tea rose gets killed. In other words, in early spring I prune off dead wood--but not because pruning in and of itself is a good thing.

Kate

I was going to say the same thing earlier today, but chickened out because maybe you folks in the cold zones have to do things differently.

Really, 12-18 inches is a very aggressive pruning in my zone. I typically do spring pruning at 3 feet. If the rose happens to be shorter than that, then I leave it alone, except for cleaning out any dead wood. There are some roses that I don't even prune to 3 ft (QE - about 5 feet).

Being one of the "folks in cold zones" I thought I'd chime in as well. I agree that there's no reason to prune your roses so low, particularly if they're already healthy and growing. I don't think a hard prune is going to make them any likelier to regrow those blackspotted leaves, except in the sense you'd force it to grow entirely new canes to replace the canes you cut off. You could do an "aggressive deadhead" type of prune, where you cut down wayward branches to reshape and tidy the plant, like you do with most Austins, but don't take off more than 1/3 of the branch unless you have to.

The exception for those of us in cold zones is to make sure you check mature canes and near the base of the plant for undetected winter kill that will work its way up or down the plant if not pruned off. That's usually the advantage of pruning in the spring, so you can notice those nasty purple or brownish splotches spreading on branches that are doomed regardless. If the lower branches are between leaves from BS, that might offer you the same (dubious) benefit of being able to find the canker. Otherwise, enjoy the taller than usual roses for this short and mild winter past!

Cynthia