Last season I planted purple cauliflower which I understand is really a form of broccoli. I live in central Pennsylvania and started my plants indoors from seed June 1. Come July 10, I set them in the garden and they done great. The heads were huge and it tasted like the best broccoli the wife and I ever tasted. It does turn green when cooked. The wife ask me to grow it again this season but she didn't have to ask! I will indeed grow a dozen of these plants each year in the garden from now on. It's that good! They also have cheddar cauliflower which I may also try but I would imagine it taste about the same as the purple :)
Rich from PA Zone 5-6