I'm not an expert by any means, but I looked the same thing up a while ago because I saw several Austins at a local nursery doing that and I was curious as to what was causing it. Suposedly it's most common with OGRs, but most of what I read pointed to cold temps and/or over-feeding, and I read something not long ago that said too much alfalfa will do it.
I have had some really mild bull-nosing on a few blooms on my Double Delights, they are shorter buds that are squared off and waxy along the edges. They go on and bloom but make a flatter shape...right on the same bushes as classically formed buds and blooms. Who knows?

I just double-checked and found this thread also:
http://forums2.gardenweb.com/forums/load/rosesant/msg051830076224.html

Here is a link that might be useful: rose proliferation

This post was edited by racin_rose on Wed, Jul 10, 13 at 12:29

Well that may very well be true as I feed them a lot of Rose Tone recently and that contains high levels of alfafa. I'll cut down on it some and see if it improves my blooms.
Thanks!!

Good luck, I think that's what I did to mine because after the first time I made alfalfa tea and saw the almost immediate results, I may have gotten just a little happy with it when you factor in the fish and guano also...so I've cut back a little and have started only feeding a couple days after a really good, deep watering. I don't know if that's right, but I thought if maybe the soil was nice and damp and the rose wasn't as thirsty, maybe it wouldn't gulp up the sauce as bad. We've also had whiplash temps here in the PNW...up to 80 in the day, down to low 50s at night.

Good luck, I sure hope it works out for you!

My roses have looked the same in the past. Did you check for Thrips. Those nasty little things cause this kind of damage. They like light colored roses the best but will go after other colors too.

The two roses on the right appear to be exhibiting balling. Perhaps the top left as well, but it's hard to tell with that one

The center top and probably the bottom left appear to be exhibiting what is called phyllody.

Both of these conditions can be caused by various adverse environmental factors (too cool, too hot, too wet, too humid). If that is the case, it will usually clear up when the environmental factors return to normal.

However, phyllody in roses can also be associated with viral infections or, much more rarely, with phytoplasma infections. So I would be watching those bushes more closely.

In any case, I would be deadheading those blooms - they're not going to get any better.

Not sure what is going on with the bottom center rose.

They look a lot like what many of mine are doing. We had a ton of cool, gray, wet weather and I attributed it to that. Now we're have very warm humid weather so they're still balling. I think the dampness is the biggest cause.

The bottom three roses look like thrips damage to me. I get this on my Evelyn roses and maybe a few others in the spring. I use a granular insecticide just one time around the base of the plants, and it drastically reduces the occurrence of the damage. Diane