Unless the area is really moist, I don't think it will get that big. The wetter and sunnier it is, the bigger it will get.

On our previous rescues we have found quite a few cin. ferns in dappled shade and moist soil, often along a creek or in a low spot. However, they are supposed to do well in sun if there is a lot of moisture. Unfortunately, I have not had luck with them in my yard...too dry, I guess. Royal fern, which is also supposed to like moisture, does just fine here, surprising me. I have my last cinnamon potted up to give away as a door prize for an event this fall. Maybe someone can offer it more moisture than I can. Good luck with yours.

Give them two years. They need moisture but they have very vigorous roots and might find it. It they do take off, they will take off! They spread by runners and will fill an area. Mine got more like 40 inches tall, never five feet. I think that would require ideal circumstances which you don't have.

The two that I grow are are in the 3-3½ ft. high range. That is fairly typical for the the species in the SE.
In their manual: Field Guide to the Ferns & Other Pteridophytes of Georgia, Snyder & Bruce list it's height as a variable between 2 & 4 ft.
This fern can tolerate almost any type of soil and habitat, as it is found throughout the state.
One of mine has grown on the elevated soil near the trunk of a White Oak for about 20 years, while the other one is in a 7 gal. pot, on concrete, under a Water Oak. It has grown there for about 10 years, since being rescued from a construction site.
They often go into early dormancy, in late summer or early fall, when rainfall is inadequate, but emerge again in spring.
Rb

These are beautiful! I've never seen them before. Will they grow in zone 6?

tami....
They would be hardy in Zone 6 and in much lower temperatures.
Check the distribution map on the link and if available, click on your state for the county distribution.
Rb

Here is a link that might be useful: Cinnamon Fern