Had the same problem in a place that I decided would be a garden. Problem was that it had so much clap seeds cooked and water washed off. It was so bad the saw briers died.
The first year I tried to turn it to break the hard pan. It brock the plow.
I planted on sratched dirt black eye peas that I bought from the grocery. What came up I tilled into the soild while green.
The next year I was able to get a couple of inches deeper and planted suger snap in the spring and then buck wheat later. Both I tilled in while still green.
The third year was easy plowing and rich soil. I still tilled in early for maximum richness. By the end of the third year people were saying that it was easy for me to grow stuff I had good soil, If they had that soil they would too.
The main help was when I was able to get a shank drill to rip up for drainage. I ripped it but what the big benifit was organic leached down and the good stuff went with them (Worms nad such) that got them deep enough to survive the heat.