Short, Sweet Vidalia Season Could Grow : Onions: Growers hope to find a way to store their crop year-round, starting with ‘sleep’ tests.

Some Vidalia onions will take a nap for science this year. Researchers will subject Vidalias to various temperatures, humidity conditions and gases in hopes of providing a year-round supply.

“It’s sort of like bears hibernating,” said Albert Purvis, horticultural research leader at the University of Georgia’s Coastal Plain Experiment Station, where the $800,000 onion lab is located.

“If you’re not active, you’re not consuming what you’ve got stored in you,” he said. “The deterioration of the onions, other than being attacked by pathogenic organisms, is by it burning up the sugars in it and dwindling away to nothing.”

Vidalia growers already store their onions for four to five months using controlled-atmosphere technology borrowed from the apple industry.

That seems oddly appropriate. Vidalias, growers advertise, are sweet enough to eat like an apple.

But, Purvis said, “We really do not know what the optimal conditions are.”

Researchers will place onions in airtight rooms where they can vary the atmosphere, the humidity and the temperature. Besides guaranteeing a more consistent supply, longer storage would mean that growers could hold out for the best prices.

Before Georgia’s first controlled-atmosphere onion storage building opened in 1989, growers had to sell their onions during the five-week harvest season from late April until early June. Prices would drop drastically about two weeks into the harvest because of a glutted market.

Growers have already been helped tremendously by the technology. Onions have gone from a $20 million-a-year crop to a $50 million-a-year crop and growers have expanded their acreage.