A friend of mind gave me some seeds from a 10ft giant sunflower that mysteriously grew in his veg patch several years ago. Since then I've been growing them, harvesting seeds and continuing the bloodline however I'd really like to know what variety they are.
The tallest one over the last few years was about 11ft and as you can see from this year's batch, they've done pretty well too. Any help in identifying would be really appreciated.
Thanks in advance,