I assume you want them for fall and winter ornamental color?
From seed? I don't have experience with them or with Georgia summers, but what I read is:
Direct sow seeds 3-4 months before you expect full sized plants.
Also, you must direct sow at least 6-10 weeks before average first frost.
If you start in cells or small cups, pot-up as soon as any true leaves appear. They do not like being pot-bound at a young age.
However, they are still cool-weather crops. If your summer is too hot 6-10 weeks before first frost, (or even 3-4 months before) you have a problem.
It sounds to me from READING like maybe you should start summer plants in the coolest spot you have, maybe shady, maybe with frequent spray watering, as soon as you think it's cool enough for them to avoid bolting.
If you're growing them for edible leaves during a spring season, my guess is to treat them like slow-growing broccoli or cabbage. Figure out how early you can plant or start indoors. They should be able to take cold weather (maybe even a light frost?) , but if you need 3-4 months to grow full-size plants, you should count backwards from "when summer gets hot".
If your winters are so mild they might over-winter and come up again in the spring, I have no idea. But I didn't think ornamental kale were likely to stay tender for long.