Winter Cauliflower

Over the last few days I had not checked the two cauliflower plants growing in a concrete planter on my front porch. When I did I discovered both have heads that have appeared in the midst of the freezing weather we've had. Normally, the large leaves of the cauliflower plant are pulled across and over the heads and tied in place to protect them from sunlight, producing the typical "white" cauliflower we see in the stores. These heads are slightly yellow since they haven't been protected: (this is actually two shots of the same head)