It's a Costus. It used to be classified in the ginger family but not anymore. They are still referred to as spiral ginger. I can't really tell which costus it is. Eventually, small flowers will emerge from in between the petals. It's easier to identify then. Costus are great plants. There are not that many that are hardy in your zone and none that I know of would already be blooming so this plant was protected during the rough winter we all had along the Gulf Coast. Good find.

Steve

After looking at your picture again, if the flowers come out yellow, I think it is Costus Barbatus based on your description of the height. It's hardy to at least zone 9. Might be root hardy to 8b. It usually blooms on second year growth so if protected during the winter and it doesn't die back, it starts to bloom in the early summer. Occasionally, you can get it to bloom late in the summer or early fall on first year growth. This is a great Costus and needs a wide area as it tends to lean and will migrate away from the original planting site over a few years.

Steve