has anyone successfully grown these in the Dallas area? If so what did you do special. I have mine in containers with lots of organic fertilizer.

I have grown both broccoli and cabbage here and it did fine. I had it in a prepared above-ground bed and fertilized it only 3 times per year with regular organic fertilizer and regular foliar feeding every other week with a fish/seaweed mix. Nothing extra special but I always mix in some horticultural cornmeal with my bed preparation. You should be able to grow it right now just fine, with no problems. The only reason I don't have it this year is because I just moved and haven't had time to put in a vegetable bed. I wouldn't hesitate to plant it now if I had the time.
Happy growing!