You can follow the blooms in my garden via this blog http://agrowingcuriousity.blogspot.com/

Try to find some Swamp Sunflowers (Narrow Leaf Sunflower) for a showy 2-3 weeks at the end of September. They grow very tall if not cut back in July (prior to buds setting). They look like a very tall yellow daisy or Black Eyed Susan. They don't have the huge center of a classic Sunflower.

I trim mine to about 2 feet off the ground in July to keep them from growing to 8-10 feet in height. They end up a gorgeous 5 foot bouquet. The more sun you give it, the more blooms you will get.
I grew them alongside the house in Charlotte with no problems in well drained soil. However, they can also handle boggy soil.

If in Charleston, pick up a Christmas Senna, Winter Cassia Senna. Gorgeous orchid-like flowers which bloom in November. Your last blooms are during Thanksgiving. The plant dies back in winter but will return. They are found easily in Charleston but I may have had the only ones in Charlotte.