Fennel (Foeniculum vulgare) is a perennial herb that belongs to the carrot family. Though its thick stalks with feathery leaves and bright poofs of yellow flowers are native to the Mediterranean region, they grow wild on the side of roads everywhere from Italy to California to Australia, where its earned full-on invasive weed status.

The most common cultivated fennel plant is called Florence fennel, and most parts of the plant are edible: while the hollow fennel stalks can be a bit tough, its edible white bulb is treated as a vegetable and its leaves (which are similar in consistency to dill), fruits (colloquially called seeds), pollen, and essential oils are incorporated into dishes all over the world.