Big Moose is available from Johnny Seeds and is said to be able to get to 200 lbs. I originally got Big Doris from Johnny Seeds but they no longer carry them. Big Doris is said to be able to get to 40 lbs. and I have had 30+ lb. ones in the past. Both should do very well for you in Oklahoma.Is Big Moose a variety? And is Big Doris? Where did you get the seed? Would like to grow those!!!