Brassica oleracea in its wild form grows along the chalk cliffs and rocky coastlines of western Europe, where it has been gathered, selected, and slowly transformed over centuries of cultivation. The plant forms a loose rosette of large, fleshy leaves — blue-green in color, thick enough to store water and nutrients against the salt wind. It has been crossed and selected so many times, and in so many directions, that today's kale, broccoli, cauliflower, collard greens, cabbage, and kohlrabi are all essentially the same species shaped by human preference. This is a lineage of extraordinary range, and the wild type sits quietly at the center of it.

Growing 10 inches to 2 feet tall in zones 6 through 9, wild cabbage performs best in full sun with nitrogen-rich, well-drained soil. The leaves are edible, boiled or steamed until tender, and the loose, open head looks genuinely different from its cultivated descendants. Seeds of the true wild type are difficult to find, which makes this more a botanical curiosity than an edible crop for most gardeners, but the plant rewards those who grow it with an unusual sense of perspective: this leaf, unhybridized and unimproved, was the starting point for one of the most diverse and globally important food plant groups humans have ever cultivated.