New boys on the block

Usually I grow plain ordinary sunflowers. They may be tall, they may be short, they may be big-headed or not, but they are all yellow and they all form seeds for the birds. Sort of like this one:

But notice the not-very-yellow sunflower in the background? I bought a packet of mixed varieties that are more ornamental in nature, the kind of sunflowers you might see at a farmers market. Sort of like these:

I recently learned that some of those fancy coneflower varieties do not make seeds, so are of no use to the birds. I am wondering if these fancy sunflowers will be seedless, too. No matter - their pretty faces are a nice surprise in the garden.