I find that shasta daisys, daylilies, Michaelmas daisies ( asters), cranesbill ( hardy geranium like Rozanne) and Lavender all work for me in front of my poppies. I'm in zone 5b, Ontario Canada. All of those plants come in color ranges suitable to your color palate. There are many more bushy perenials that work in front of poppies, but these are the ones I have used the most.
