I have a row of roses and I have maybe 1-2 ft of space in front of them and I really want to plant things like daisies, phlox, columbine, and campanulas in front.

In my experience plants take as much space as they need regardless of the amount allocated by the one who plants them. I normally allow sufficient space between plants to allow them to reach their mature size but it isn't possible to plan for the "surprises" that inevitably occur. One named hosta cultivar I bought years ago ('Kiwi Full Monty') was supposed to grow 28" in diameter. Mine are closer to 48" in diameter. Since I purchased my hostas from a reputable local hosta grower, I didn't anticipate the super-sizing and had the hosta dug out of the bed where it had grown to nearly block my granite path. I'm now dividing it again and planting it as a "skirt" around the base of a mature oak tree.

I didn't plan for or consciously choose the cottage garden look. My cottage garden beds have done it on their own.

I planted some dark red gaillardias in front of some cleome and the white cleome are covering them up--they are getting so bushy while the gaillardia are staying shorter. I'm tempted to trim the lower part of the cleome to give the gaillardia more room.

I just didn't allow enough space, I mean.

Roses often do well with under-plantings and mine are all grown with other plants, but you might want to ask for specifics on the rose forum. How long have the roses been in place - are they full sized? Are they bushes or climbers? If they are new, I'd stick with low-growing annuals such as Alyssum or Lobelia maritima for a couple of years until you have a good feel for how large your bushes will get. Good air circulation can be important for healthy foliage, especially with fungal diseases in roses that are prone to things like black spot, so I would stay with shorter plants. Regular tall garden phlox (P. paniculata) are large, robust plants that would hide many rose bushes and enclose them enough that I would worry about disease on both the roses and the phlox, and mine are always larger than 2' wide. I don't grow regular daisies, so don't know about how suitable they would be (I think they might spread too much and thinning them would disturb the roses), but there are smaller varieties of Campanulas such as C.cochlearifolia, C. carpatica, C. rotundifolia, 'Birch Hybrid' or any of the 'Clips' series that would work well. Even if they spread under the roses they are shallow rooted and won't compete. Columbine would be fine since it blooms on airy stalks with the foliage staying low. Here are some other plants that would work well in front of roses.

Veronica 'Georgia Blue' - low, delicate foliage, intense blue spring flowers with occasional repeats in late summer and fall, weaves gently around other plants and is happy in sun or part shade

Low Dianthus (pinks) such as 'Greystone', 'Brilliancy', 'Firewitch', 'Bath's Pink' or D. grantianopolitanus.

Scabiosa such as butterfly blue is like Columbine in the way that the foliage stays low. Long summer bloom time in my garden.

Delphinium 'Blue Butterfly' is another low-growing plant that would be fine in 1'-2', though it gets a bit taller than my other suggestions, more like 18".

You could use foliage as well; non-aggressive low plants with green and white variegated foliage would look pretty all season at the feet of the roses since the color wouldn't rely on bloom. One possibility - I have a green and white variegated thyme that seems fine with the regular moisture levels in my garden.