(Exhibition or Kelsae Sweet Giant) - Brought to the U.S. from the British Isles, this heirloom onion is by far the largest onion you can grow in a short growing season. If you are looking for show-size variety with which to win the county fair for largest onion, this is it. They have gotten as big as 6 pounds. Open pollinated, stores approximately one month, matures in 95 days, globe-shaped, yellow.