By George E. Boyhan
University of Georgia
A Vidalia onion, though, is really one grown in a specific southeast Georgia region. The Vidalia name comes from the city in the heart of this region.
The name Vidalia, for the purposes of marketing onions, is owned by the Georgia Department of Agriculture. The GDA grants permission to growers in the region to grow onions and market them under this name.
The region where these onions can be grown encompasses 12 whole counties and parts of eight others. Growers inside this "onion belt" can grow and market Vidalia onions. Anyone outside can't.
Federal, tooBesides the state recognition, there's also a federal market order for Vidalia onions. This gives federal recognition to this region and its sweet onions. The market order also allows the Vidalia Onion Committee to collect funds from growers for marketing and research.
So, what about these sweet onions? What makes them so sweet?
To begin with, the type of onions is vital. Farmers in this region grow short-day onions. All onions form a bulb (the part you eat) as the days grow longer. Onions here form this bulb with relatively short (11- to 12-hour) days.
Onions grown in more northerly latitudes are called intermediate or long-day onions. As you may have guessed, they form bulbs at even longer days. So, they're planted in the spring and harvested in summer or fall.
Short, sweet daysBecause our onions bulb with short days, we grow them as a winter crop. These short-day onions are known for their exceptionally mild, sweet flavor.
Within this onion type, 25 varieties of sweet onions can be officially grown as Vidalia onions. These must undergo three years of University of Georgia testing before they can be approved as Vidalias. The GDA makes the final decision for any new varieties to ensure quality, mild, sweet onions.
Besides the varieties, southeast Georgia has the perfect combination of weather, water and soil to produce Vidalia onions. The winters are the perfect weather for onions: cool with not too much freezing temperatures.
The region has plenty of irrigation water from large wells. And water is critical to producing a mild onion. Without it, the onions remain small and can be hot.
Finally, the region's soils are perfect for onions because they're low in sulfur. Sulfur helps make onions hot. It's from the sulfur-containing compounds that onions develop their pungent taste.
The bottom line is that this southeast Georgia growing region has the perfect combination of conditions to produce the world's sweetest onions.
(George Boyhan is a Cooperative Extension horticulturist with the University of Georgia College of Agricultural and Environmental Sciences.)
(George Boyhan is a Cooperative Extension horticulturist with the University of Georgia College of Agricultural and Environmental Sciences)