500 Treated Vidalia Sweet Onion Seeds Non-GMO Heirloom These Early Grano Onions are a Vidalia Onion variety and are considered mild and sweet. Though they can be grown in any area of the country, Texas Grano Onions are grown heavily in the South and West. They are a short- day variety of onion. As an annual crop, they are slower to bolt and are considered a great producer. This variety is more resistant to thrips and pink root fungus. This means they can be stored a little longer than other short-day varieties.