Veronica Gentianoides works well in rose beds. I first saw it a few years ago in a Manor house rose garden and bought one and I am pleased with the results every year with very pretty flowers in May.

Thank you for the tip

Depending on your soil, gypsophylla always looks good with roses and, of course, good old lavender. My beds were rather wet last year, so thought of trying white viola cornuta, not flowering yet so can't say how it will look:-)