Ann,
Aren't they great! I feel they add a lot to sunflower bouquets, and wish I had grown more, but I had only saved one stalk last year, and stuck it in an old crock. It wasn't until spring I was trying to get seeds from it. I cut mine last year when I noticed the birds were starting to pick at them, but ended up cutting some too soon. I would say when you can actually see all the seeds lining the bloom part, that's when you pick it. I was very happy to see they come true from seed because that seed is expensive. I only have about 10 stalks, so I'm saving most for seed for next year, so I can grow more. Another really nice addition to the sunflower bouquets is "hot biscuits" amaranthus. I have also been adding crocosmia.
Cheryl

Cheryl,
Thanks for your reply. I guess I'll leave the oldest ones on the plants, and continue cutting the rest for bouquets. The older ones may then be able to make mature seeds, but I'll have to keep watch so that the birds don't eat them all, unless I bag each one!
Ann