It’s six foot tall, and the flower is the size of your head –

Admire it now, as it’s only a matter of time before the squirrels find it. And destroy it.
We tried one year to harvest the seeds. Read up a bit and tried a tip on how to keep the little buggers out of the seeds – “Put a paper shopping bag over the flower, so they can’t find/get to the seeds” it said. So yup, there were a handful of giant sunflowers with paper bags over their heads in the garden. Looking for all the world like they were ashamed of their football team. Then one day I noticed one of the bags shaking around, and you guessed it, the squirrel was in there have an absolute FEAST. Ate every single seed and left all the shells in the bag. At least it was easy enough to clean up.
Silly rodents. Smarter than me I guess.