I planted the seeds directly in the first half of May, after that it's just a matter of keeping them watered and watching them grow. They are right at the edge of the vegetable patch, so they won't interfere with end-of-season work on the rest of the patch, things like tilling, spreading manure, sowing cover crops etc. They will stay where they are through the winter, and the birds will have them picked clean by the new year. My only concern is the possibility of attracting rats, so the barn cats had better be on the job.
I grow the big sunflowers strictly for the joy they bring to people who visit, and to me as well...