I've never made frequency of bloom a factor in deciding what to plant where. My considerations are only habit/needs of plant (including the question of runners) and color of flower. Truth be told, I had never heard that folks made this sort of separation. Interesting!

feh - didn't even know there was such a rule. Mine are planted willy-nilly according to space and desired effect - the number of bloom cycles (we usually only ever get 2 good ones anyway)never enters my thinking (like a lot of things).

To my eyes the colors of some of the more modern roses clash badly with the OGRs; repeat bloom is not a consideration.

I wish my thinking were so orderly, and that I didn't so often simply need to get roses in the ground in a hurry. For me it's not so much once bloom vs. repeat bloom, but whether foliage and style fit together. Also, mixing roses up thoroughly is better than having one rose of a different type in the middle of a long bed all of a kind: I was relieved when my husband finally dug out 'Bonica' from a bed of once-blooming old roses. ('Cornelia' and 'Souv. de St. Anne's' are still there, but don't stick out as much.) But I could happily see reblooming Portlands, for example, mixed in with Gallicas, Damasks, Centifolias, etc.
If you are going to have a very mixed up planting of roses, then added a lot of other plants will distract from the heterogeneity of the roses. Final thought: roses of different characters can go fine together, or not; it all depends on the specific varieties in question.

I have no rules and mix all kinds of roses if the colours go together. I especially like mixing flatfaced singles with doubles, and large and small blooms together. In larger borders I place onceflowering species or near species at the back with reblooming roses and perennials in front of them. This way I get the best of both worlds. All will bloom together at least at the beginning of my rose season and when the onceblooming roses are over, I still have the remontant roses in bloom.

I actually prefer the mixed look. I have noticed that in my garden the once bloomers usually have a more luxurious look to the foliage so that they often cover the scraggly look of the more modern HT's.
Just a thought.
Jeannie

I was going to say exactly what Jeanne said.

My ramblers on the fence (once bloomers) provide a beautiful green leafy background for the tea roses that are planted in front of them in the same bed. In my soon-to-be Labyrinth garden, my plant list contains Gallicas, Hybrid Chinas, Musks, Chinas, Teas, etc., etc.

It's all about HOW you use and arrange the roses ... and not so much about whether the roses you use are once blooming or repeat blooming. Think about it this way ... most of the rose is green anyway. (even if it's a repeat bloomer) Use the size and texture and color of the leaves, in addition to the color and frequency of the flowers, when you design your gardens.

I never even considered that..I think I have more once bloomers than repeat bloomers, but I tend to arrange them by size, and keep the thornless ones where people are most likely to bump into them.

In some areas, I put the larger once bloomers (like damasks) behind the smaller repeat bloomers...mixed in with perennials, annuals and herbs. In other areas, there are once bloomers and repeat bloomers just placed wherever they look good, with the other shrubs and flowers.

Our summers (July and August) are so hot, we don't always get a lot of repeat blooms, anyway...so May and June are the best times for roses. Another reason for all the other flowers and herbs :)

I've done what Lavender lass does. My once bloomers are usually larger so they go in the back and the shorter/smaller repeating moderns go in the front. I didn't know there was a rule that said you couldn't mix OGRs with moderns or once bloomers with repeaters so I just mixed them all up!