Centranthus ruber "Coccineus" (Jupiter's Beard, Red Valerian, Keys to Heaven)
Some may consider Centranthus ruber, or Jupiter's Beard, old-fashioned, but it is still popular for its ease in growing, its non-stop blooming, and the lovely cut flowers it provides. This rose-colored variety grows from one to three feet tall in sun/partial shade (it may get floppy with too much shade) in Zones 5-10. And, as you may have noticed, butterflies enjoy it, too. Quarts.
Centranthus ruber alba White Jupiter's Beard, Keys to Heaven
This one has the same growing habits and requirements and the same endearing qualities as the Centranthus above, but just in white. (Photo from Wiki Commons, licensed by Creative Commons Attribution Share-Alike 3.0 License)