From one 9b to another, it's not too late to start if you are starting with plants rather than seeds. Summer veggies are tomatoes, peppers, okra, green beans, melons, squash, and more. Yes, you will have to pull stuff to make room for fall vegetables. My problem last year was that the summer vegetables kept on producing, so I didn't want to pull them out. You could plant the fall vegetables, which should be planted in late summer between the summer veggies, but then you would cut off the summer veggies when they're done rather than pull them. If you pulled them, you would disturb the roots of the fall veggies.

For more information, check out your local Master Gardener website. They would have information on what grows in your particular location. If you don't have a local MG group, our website has info. uccemg.org

Here is a link that might be useful: What's Growing On?