A plant in the Asteraceae family (meaning its related to sunflowers), it is a thistle. There are cultivated varietals, including artichokes. However, I will be focusing on the uncultivated cardoon.
The plant is both herbaceous and perennial. In certain cases, the leaves are edible. The stocks are edible, but this is only true of the innermost, white stocks. At key trait as a plant is that it is a hardy one. If you’re considering one for a garden, apparently the flowers are particularly attractive to bees.
The thistle of this plant can be eaten as a small artichoke. A more common use, though, is to boil or steam the stems of the cardoon plant. In this regard, it is commonly used in Spain, France, and Italy. Aside from those countries, cardoon is mostly used for culinary purposes in the Mediterranean region.
Additionally, cardoon can be used as rennet in cheesemaking. The practice was recorded as far back as 70 CE in Rome; the practice itself is probably older. A more recent development is that cardoon has been considered as a crop for biomass as a type of fuel. As stated before, it is a hardy plant, but it is also a fast-growing plant, requiring little in the way of input. This makes it an interesting candidate amongst crops that are already being cultivated.