These are nerve-wracking days for orange farmers.
Orange crops in Florida and California—by far the country's two largest producers—are fighting battles on almost every front a farmer can face. As boxes of California citrus fruit rot on the docks amid dragging labor disputes at the state's shipping ports, Florida growers are concerned that a blast of frigid air that's expected to hit the state on Thursday will freeze next year's orange crop before it even grows.
Freezing temperatures are expected to all but completely blanket the Sunshine State over the next 24 hours, and temperatures may fall below 20 degrees in the center of the state, where many of its farms and groves are located, according to Nicole Carlisle, a meteorologist with the National Weather Service based in Tampa.
Many crops are threatened, but orange growers are concerned that one day of bad weather will cut into two years of harvests.
Here's why: Growers in the state have already harvested about half of this year's total crop, said Marty McKenna, an orange grower and chairman of the Florida Citrus Commission. But the rest are still on the tree. Oranges can withstand temperatures of about 30 degrees for up to four hours. Growers can also spray the tops of the trees with water, which forms a layer of ice and keeps cold air out of the fruit. But the flowers cannot withstand freezing temperatures at all. And next year's fruit will grow out of this year's flowers.
More from CNBC: The world's most expensive food?
"I would say almost every grove from one end of the citrus belt to the other has trees in some stage of open bloom," McKenna said. "It's highly unusual and I can't remember a cold snap hitting when the trees were already flowering like this."
"For the bloom on for next year's crop, we will have to go out on Friday morning and see how the trees look," McKenna said.
All of this is happening as the state is waging a long and increasingly expensive war against citrus "greening," a disease caused by a bacteria carried by tiny insects. There is no cure, despite the fact that the citrus industry has spent piles of money to find one. McKenna said it's a bit like cancer research in that people are throwing money at the problem and scientists are making progress, but no one has actually found a real answer yet.
More from CNBC: Refinery explosion threatens to hike LA gas prices
Despite the trouble, McKenna's outlook is not dire. "We are still down here, and we are still producing oranges," he said. "Nobody's quitting, nobody's throwing arms in the air. And we will get a solution, we just don't know when."
Things are more desperate for California citrus farmers. The ports slowdown is stalling the shipment of oranges and other citrus to Asia—a market that collectively buys around 25 percent of the California orange crop. Oranges are particularly popular during Chinese New Year—which is Thursday—as a symbolic and festive fruit. China, including Hong Kong, is the second largest market for California orange exports after South Korea.
"The ports slowdown is having a very significant impact on our business and has the potential to be catastrophic if it continues," said Bob Blakely, vice president of California Citrus Mutual, a group that represents citrus growers in that state. "We are into the peak of our export season, and this week our shipments were off 50 percent compared to the same week last year."
Total exports could be down as much as 50 percent for the entire year—exports account for about $500 million of a total $2 billion in citrus sales for the state, Blakely said. The fruit that is making it to Asia is delayed and in poorer shape than it would otherwise be. Blakely said he has heard some accounts of shipments taking 40 days to reach Asia or Australia—almost twice what it should take.
If the disputes at the ports drag on, the domestic U.S. market may be flooded with oranges originally destined for Asia, driving down prices. Already, growers are cutting back hours for harvesters, who in turn depend on the peak harvesting season for the wages they get from long picking shifts. Growers cannot import tools they need to harvest the rest of their crops—the nets they use to harvest mandarin oranges are made in China.
This worry comes amid a dry winter in what has now become a six-year drought for the state. Many growers have already exhausted their well water and may not be able to grow a crop at all next year, Blakely said.
As for this year's crop, Blakely worries a lot of it will simply "fall off the tree and rot."
This could mean the 2015-2016 crop of oranges could be a lot smaller than planned. It is hard to put a number on the potential damage, McKenna said.