While most residents of southern Wisconsin have enjoyed the early spring weather in recent weeks, area fruit growers are stressing these days.

Thursday night's chilly temperatures were in the danger zone for some crops, prompting many to worry about how their plants will fare this season. The early warm weather brought the buds out on many fruit trees, leaving them vulnerable to a freeze.

In Madison on Thursday night, the official overnight low was 26 degrees. For a budding apple crop, the critical temperature is 28 degrees. Below that temperature and the plant's pistil -- one of those tiny pieces inside the flower -- could freeze and die, which will result in no fruit growing.

At Eplegaarden Orchard in Fitchburg, the 20 acres of apples make up the largest portion of the orchard's business, and losing them would be a serious hit to their budget. So, the team of apple growers got resourceful to ward off such a calamity. They lit bonfires around the orchard at about 2 a.m. on Friday. As the air flowed down hill in the orchard, the heat from the bonfires helped keep things from getting too cold at the bottom.

"We had 11 people out here. Everybody got up between 3 a.m., 4 a.m. and we had fires set out in different spots. Set people up in pairs and people just went at it keeping the fire going until dawn," said farm manager Rami Aburomia.

Their efforts were enough to save the bulk of the crop for the season, but they're still worried about what's to come.

"It looked like we did OK," Aburomia said. "The problem is we've still got the whole rest of April, May, and it's hard to predict if we're going to get more cold temperatures or not."

Aburomia said they plan to repeat the process when temps dip again next week.

Orchard workers also used propane heaters to keep some of their trees warm.

If the temps were to dip as low as 20 degrees, there'd be little hope and little reason to exert much effort except on a small group of trees that grow the orchard's most popular apple, the honeycrisp, WISC-TV reported.

At Wollersheim Winery in Prairie du Sac, Philippe Coquard worked from 1:30 a.m. to 8 a.m. Friday to keep the cold temperatures away from his vulnerable vines. He used huge fans to keep cold air from stagnating in low areas and used a heat-creating "frost dragon" on other parts of his property.

"The issue is not so much the spring frost. The issue is how far along the buds are because of the warmest March in history," Coquard said. "(The warm weather) was beautiful, but it's not great for agriculture."

Coquard estimated he lost 10 percent of his crop overnight, and it would've been worse without the extra equipment, he said. He's considering setting small fires throughout his 27 acres next week, when temperatures are forecast to dip into below 30 degrees again.

Fruit growers across the Midwest are in similar predicaments, said Lee Jennings, an agriculture expert at the University of Wisconsin-Extension.

"Your apples and grapes, they're in a pretty tender state of development right now, so it is pretty serious," Jennings said. "If we lose blossoms, there's no way to regenerate those, and we could lose a lot on yields."

Some fruits may be in short supply at the grocery stores, making them more expensive to consumers, Jennings said.

At Wollersheim, Coquard said his business can survive without 10 percent of its crop, but he's concerned about more damage next week.

"If we lost 50 percent of the crop, it's a huge loss," he said. "That's 50 percent of the business, and we cannot buy those grapes anywhere else."