Sunflowers look great in a vase but are heavy drinkers and need conditioning in a dark place overnight after cutting.
I have tended to drift away from growing Sunflowers but now I think my reasons may not be correct.
I tended to grow tall varieties which produce one or few flowers. They were showy but needed support from the wind in our northern hills.
The knew the space was better dedicated to other plants and the only sunflowers that grew this year were self sown from our bird feeders (and the flowers were small weedy efforts that I should have pulled up).
North Carolina University Sunflower trials
Harewood House near Leeds has been conducting trials of Sunflowers and this variety was well finished by the first week in September.
Sarah Raven Grows Larger Cutting Sunflowers
State flower of Kansas North Carolina University Sunflower trialsRead more on gardenerstips.co.uk