I've always subscribed to the belief that true red goes with everything. Although these Astrantia flowers are more of a raspberry shade, they mix well with the peach-colored rose. I think it's because the roses contain smudges of raspberry in their petal composition. (At least that's my theory.)
Blue is the black for peachy shades. Of course true blue is almost impossible to find in the floral world. One of the closest is a Veronica called 'Crater Lake Blue', a somewhat sprawling plant that reaches around 12". I wish I knew the name of this Agastache with orange flowers. It's blooming and standing up pretty straight considering it's sheltered from the sun more than is optimum. The surprise is how well it goes with the rose. Yes, it's the same one as in the photo above--Rosa Oso Easy 'Peachy Cream'. Also in the vase are Ornithogalum magnum (the white flower) and Clematis 'Rooguchi', the purple bell flower that is really out of scale for the arrangement.