Giant Red Mangel Beetroot (B. vulgaris)

Giant Red Mangel Beetroot (B. vulgaris): literally "giant" beetroot, cultivated as early as the year 1000 as a variety for both fodder and human consumption. Despite its appearance (when left to mature, it can exceed 1.5 meters in length and weighs several dozen kg), it is easy to grow, though loose soil is essential for its development; it suffers either waterlogging and overwatering. Sown in autumn, it will only need irrigation in cases of prolonged drought. It is frost-resistant, even if it loses the leaves they will return with the first warm weather.
It is completely edible both, the green part (sweet and very fleshy leaves) and the gigantic root. You can harvest it when it weighs around 4 or 5 kilograms (already considerable size), or let it grow to full size: at that point it will be tougher, better suited for fodder, to the delight of your animal friends.
Also suitable for beginners and those looking for an excuse to talk about their garden.