Hi Lorna, :D
we do both ::) the flowers in the pics grew from seed heads that we left lying on the ground, for the birds to peck at. We also dry lots of heads off, simply by hanging them up on the fence or, if it`s wet, inside somewhere. Then when dried off a bit, scrape the seeds off the heads & put them on the bird table. You can also keep loads of seed this way for later on, or for sowing next year.
Adrian.