Sunflowers are sure easy. I surrounded my entire garden with them this year, and when they are ready, I'm cutting the heads off and drying them, so I can put a head out in the dead of winter and let the birds snack on something relatively fresh. All I did was plant them per the packet -- I did several varieties -- and add support as needed for the tallest ones (like 12 feet tall). I did not water, but we had plenty of rain this summer.
As far as free range...LGDsI'll make sure mine get food so they can keep the chickens safe.![]()
I dare say I would also select for birds capable of looking after themselves. My Silkies and birds that won't free range would be the first to be eaten, except for maybe a couple broody hens. The Swedish Flower Hens, a breed created via natural selection, would likely be the ones that I keep.
Don't forget to store some heirloom seeds you could grow. Modern hybrids won't allow seeds to form or they don't grow well, so you can't save seed year to year.
BOSS (Black Oil Sunflower Seeds) is what you want to grow/feed your chicks...the other giants and ornamentals are not nearly as rich in protein as the boss.