When I bought this stalk of Brussels sprouts, I wondered about the wild plant it came from. Did you know that cabbage, broccoli, cauliflower, kale, collard greens, kohlrabi and Brussels sprouts are all the same species? Every one of them is a cultivar of Brassica oleracea, also called wild cabbage.
Wild cabbage is a biennial that grows naturally on limestone sea cliffs in Europe. In its first year it’s a rosette of leaves. In its second year it blooms. As you can see by the flowers, it’s a member of the mustard family (Brassicaceae or Cruciferae).
Ten thousand years ago humans foraged for wild cabbage leaves. At the dawn of agriculture we began to cultivate them. One thing led to another, as described at Wikipedia:
- Our preference for leaves led to kale and collard greens as cultivars.
- We liked the tightly bunched leaves and the terminal leaf bud so we cultivated cabbage from the first-year rosette.
- The Germans liked fatter cabbage stems so they cultivated kohlrabi. It’s not a root, it’s a bulbous stem.
- People liked the tasty flower buds of the second-year plant so we cultivated cauliflower in the 1400s (flower is in its name) and then broccoli.
- In Belgium they preferred the small leaf buds that grow in the leaf axils, so they bred Brussels sprouts in the 1700s.
While they’re growing, Brussels sprouts are nestled in the leaf axils like this.
As the stem gets taller the lower leaves turn yellow and fall off. Farmers and gardeners usually remove fallen leaves or prune them back.
Sometimes the weight of the plant bowls it over.
Eventually the plant is harvested and we buy Brussels sprouts in the store. Mmmmm! Leaf buds for dinner!
p.s. Did you know that Brussels sprouts are sweeter if they’re harvested after frost? Alas, most are harvested before that.
(first photo by Kate St. John, remaining photos from Wikimedia Commons; click on the captions to see the originals)