Q.cold weather & sunflowers
We live in NE Washington St. Our sunflowers have done well, but we are in late Oct. and heads have not changed color yet. The little yellow petals are just beginning to fall off, seeds still white. We have had one mild frost and temps are expected to drop this coming week to seasonal normal temps. Should we cut the heads off before the backsides or seeds change color? Thank you for your help.
Though you can allow the seed heads to mature and dry on the plants, if the time is running out on the warm dry days, it's best to harvest the heads sooner.
Here is a link that will help you.