This is a cool lesson in genetics, for you! You can learn a lot about biology, just looking at the plants in your garden.
For most plants grown from seed, even the most inbred commercial lines, there will always be some plant-to-plant variation. Many plants tend to self-fertilise, meaning they produce pretty uniform offspring, but even then - if they make flowers, they'll occasionally mix up their genes. It's more or less impossible to make plants completely uniform, without some crazy genetic tricks, or cloning (through, say, cuttings or grafting).
Most often, when an extreme cultivated plant (like your sunflower here) shows variation, it'll be more like the wild type. If you look at pictures of wild sunflowers, you'll see that they're much smaller than cultivated ones, with small seeds (too small for humans, perfect for birds). Typically they'll be bright yellow, and will have a lot of branches, and lots of flowers. We made them single-flowered, because like Megan said, it ensures big, easy to harvest seeds. So if that's what you want, then chop off all the side branches.
In our garden, over time, we just let the sunflowers seed themselves for a few years, and now they all look like the wild ones.
Are you growing from saved seed or do you purchase commercially each year? over 8 years ago.
I grow these as a hobby. I only once grew black oil seed sunflowers from seeds that I harvested from my own sunflowers seeds of which I bought in a pack. These velvet queens are the first time I am growing so I started these from seeds i bought in a pack. If these turn out successful I will be saving the seeds to grow more. I dont grow at a large scale at all, this is just a hobby so I could have beautiful flowers to observe and save seeds so I reach a complete closure with the batch. over 8 years ago.
I saw a guy on Youtube who grew velvet queens and one of his sunflowers had heads like the one on my younger plants. I have also uploaded a photo from today titled "Next day update" and you can see tiny yellow petals. So I guess this one is growing fine. over 8 years ago.