Butterfly weed, cone flowers, annual rudbeckia, rose campion
Butterfly weed (Asclepias Tuberosa)
Maybe he could charge a battery?
Bear's breeches from Goldner-Walsh
Butterfly weed, annual rudbeckia (it re-seeds), shasta daisies, red eupherbia
Lisianthus, balboa--purple, blue
Sneezeweed (Helenium)--easy to grow and control
Yellow cone flowers--also purple, white, orange hybrids