There is a thread on Garden Web discussing how difficult Persian Shield (Strobilanthes) can be in the garden. I have decided that it demands hot, humid conditions to thrive and can still fail. It's native to what used to be called Burma, between the Tropic of Cancer and the Equator.
It is such a brilliant Crayola purple when it's happy, which seems to be in mostly shade. I put a rooted piece under the hydrangeas at the end of the porch. I had to cut a hole for viewing, but the Persian Shield is happy as can be, hiding under there.
These last two photos are of established Persian Shield. They die to the ground at the first frost, but come back the next spring.