Think you would need a warm pink to avoid fighting with your roses, or mix in some white.

I have four o'clocks in a solid red and they bloom nonstop for months in heat. The flowers are pin-point size in the most blazing hours when the petals close. They live through the winter here, but in your zone I think they would reseed pretty successfully. I grew them from seed 5 years ago and they continue to pop up courtesy of the birds in new spots - still not a thug though. They also come in solid pink, white, yellow, and mixed.

Tall garden phlox, yarrow, echinaceas, some of the new coreopsis are possibilities for pink and warm shades. There are pink beebalms also since they do well for you.

I love the texture of catmints with roses, and there is a choice of sizes - six hills giant down to dropmore. It's a light gray blue, but it really sets off the apricots and soft pinks of some roses.

Have fun with your new bed.

I like to use the Nepeta (catmint) a lot in my gardens. Six Hills Giant would probably be to big for your spot though it is a gorgeous blue and blooms like crazy. Walkers Low Nepeta would be a better size and if it gets to big you can shear it back. It has a bit darker blue color but it goes with virtually any color. If you shear any of the nepeta's back when they are done blooming they will rebloom.

Thanks for the responses! I wasn't familiar with four o' clocks before this, but the pictures I've seen since are really lovely. I'm debating between those, catmint, or phlox, depending on what I find about their powdery mildew resistance. I've had *such* a hard time with that--I've tried poppies, peonies, echinacea, one variety of tickseed, and all of them became powdery grey, then brown, then dead with the onset of late summer rains. One peony tried to grow back but it was a mangled version of itself. Milk sprays have helped a lot, but even the so-called resistant bee balm has been hit pretty hard. Sorry to rant...mildew has made gardening really frustrating for me.

If I do go with catmint (or if my bee balm recovers) how would I keep it from taking over the roses? I was under the impression that I should not plant things with that spreading habit, as roses wouldn't be able to compete with them. Is that wrong?

It is not wrong regarding aggressive spreaders, but the key is the word aggressive. I wouldn't use the larger forms of nepeta, use the smaller like Walkers Low. It is easy to shear it back if it is getting to big (I do this in my container garden beds) prior to it blooming to control size. I also will shear it back after it is done blooming no matter the size to promote repeat bloom.

I wonder though since you already have problems with powdery mildew if you might want to evaluate and treat the conditions you can control before you plant anything more there. You could easily just place pretty pots of flowering annuals at the base for the color while you deal with the mildew. Crowded conditions and lack of air circulation around plants invites more mildew problems. It is hard to tell from your picture but it looks like simply pulling the garden further out away from the house might help.

Here is a link that might be useful: Powdery mildew

The roses don't look very tall. If you want them to be the main focus than try purple Bungleweed for ground cover.

I like the cottage garden. Move the Roses up front and between them put in some Space Age Bearded Iris and other spring bulbs. In the back put some Fancy Brown Eyed Susans for mid to late summer, A nice single petal Hollyhock and Phlox. Put in annuals where ever you have gaps.