I am wondering the same thing. I'm planning my spring planting, and our landlords have generously afforded us an expansion of the part of the property that we are using! We'll be moving the chickens farther back up the hill and planting food up closer to the house. I'm wanting to plant as much as I can to help offset the cost of feed and would love some recommendations!
I'm thinking amaranth (the edible stuff), quinoa, flax, sunflower seeds, corn, soybeans, and I'll be giving the chickens all the garden leftovers (extra squash, pumpkins, lettuces, etc., as well as the seeds). Not sure what else I should put in the "feed garden", which is a section I'll be using just for growing chicken food.