Are you talking about Justicia carnea? If so, this won't take more than a degree or two of frost. It roots easily from cuttings, which may be easier to take in late fall and then replant in the garden in spring. This plant gets 5 feet tall and blooms nearly all year round in our coastal California conditions, and a friend calls this one the "Josephine Baker" plant because the flowers remind him of her head dresses while dancing...

I've been growing Brazilian Plume(Justicia carnea)in the ground for the past 7 years in zone 7b. It is root hardy here, plant in well drained soil and mulch over. 7a on the other hand might be different, but if planted up against a building it might be worth a shot, mine is in the open.

Could these be used as a hedge in a shaded area? (Zone 9 central florida)