I visited Charleston last weekend and was fortunate to catch the azaleas blooming at Magnolia and Middleton Plantations. While I appreciate the ease and showiness of the Asian species that make up the bulk of the displays there, to my mind our native azaleas are prettier. Most of our species are native to the Southeast, but there are native azaleas to fit most growing conditions and zones. I also value them for their large color range (everything between white and red), their fragrance, their fall color, and their varied bloom times (Almost into fall for r. prunifolium!). 
Here is a picture of R. periclymenoides in full bloom at Middleton Garden, where you can truly see why the plant was once called R. nudiflorum, since there’s not a single leaf yet to hide those glorious flower pompoms! 
Also, here’s my favorite native azalea in my own garden, a Choptank hybrid of unknown name. It always blooms with the wild sweet william phlox. 🙂