It looks like botrytis to me. Did you have a damp Spring? I would cut off all black and wilting foliage. Throw the leaves in the garbage.

I Agree with ctgardenguy,

cut off all black and wilting foliage and any thing else that looks diseased, leaving only healthy foliage. And DON'T compost it, throw it in the garbage or burn it, and remember fall cleanup is really important to help preventing it the following year

It wouldn't hurt to use a fungicide after cutting off all the diseased stuff to help protect the remaining healthy foliage.

But definitely consider using a fungicide next Spring to help keep it healthy and nice looking, since Spring is when they are growing and flowering and need to look their best.

Agree re spraying. I use this Copper Fungicide for botrytis:

Copper Fungicide

It does a great job with black spot on roses , too.