I would not let it flower as that takes away from the root. Cut it off and go all the way down to the ground. Depending on the size of your plant now, you can wait until the fall and devide and move 3 ft away and plant it in composed horsemanure PH 5.5-7.0 !st year don't take any, 2nd year a few but the 3rd year harvest 8 to 10 weeks. Depending on how cold it is in the winter you might need to cover it with hay to prevent it from freezing. Happy summer.