Sunflowers.. The ones I started from seed are growing as a bush... How do you grow the 7/8 foot ones???
It depends upon what variety seed you have. They vary in height from Mini (’Teddy Bear’) to MONSTER size (’Russian Mammoth’).
https://www.countryliving.com/gardening/g32128958/sunflower-types/
Some of my favorites (Medium sized) for cutting or just enjoying in the garden are:
ProCut Orange
ProCut Gold
Soraya
Ring of Fire
Jung’s carries the above.