Some varieties are simply stockier than others. I've done Hawaiian #9 (silver).
This variety has thin stalks and grows to 11 1/2 feet (measured to tip of tassel). The only way I've managed to keep it upright is with a multi-level Florida weave. I plant in 4 foot squares, 4 plants 1 foot apart in a row, 4 rows 1 foot apart, 16 plants total per square, a 10-11 foot pole in each corner of the square.