Soapwort is not native but is a wonderful edging plant. Its small pink blossoms will greet you from late June until frost, if you cut them back hard after each bloom.
Rudbeckia maxima is a compact plant that bursts into bloom in late August. It looks like a yellow firecracker going off in the sky! No care. Easy to keep the size you want.
(Liatris aspera and L. spicata 'Alba')
Gayfeather is deep pink, and L. spicata 'Alba' is white. I love how their straight, stiff spikes come up through the clumps of other flowers.