Little Lanterns and Pink Lanterns are shorter varieties of columbine.
Amsonia Bluestar is a sun lover.
The Jeana variety of garden phlox is relatively mildew-free.
If deadheaded, fringed bleeding heart will rebloom.
For more plant suggestions, check out Stephanie Cohen's newest book, "The Nonstop Garden: A Step-by-Step Guide to Smart Plant Choices and Four-Season Designs." She's also an author of "The Perennial Gardener's Design Primer" and "Fallscaping."