Can't really help you, but I hope you already know of the Butterfly house in Durham. It is enclosed and I suppose temps are well monitored rather than open which changes things completely. However, they probably know all about the natives and could give you useful info. Actually, I believe they do have an outdoor portion of the exhibit.

Here is a link that might be useful: Butterfly House

You will mainly want native plants, especially Asclepias for this area, not the tropical one. Debbie Roos, extension agent in Pittsboro, has done a masterful garden there. I am copying a website, and you can scroll down and see a plant list as well as a slide show of the demonstration garden, and other helpful things. She will probably give you more advice if you email/call her as she is very helpful to everyone.

Here is a link that might be useful: Debbie Roos' pollinator garden