Potatoes: boil ‘em, mash ‘em, stick ‘em in a stew. Or don’t, because they’re in dangerously short supply. A late start to the growing season combined with an unusually cold, wet autumn damaged potato crops in the US and Canada, leaving french fry makers hunting around for spuds with which to make their wares. But don’t get too worried. Experts say potatoes will persist—even though the North American supply may be tight for a few years.
A timely Bloomberg article about this year’s unusually small harvests sparked a flurry of concern about a possible fry shortage. But to understand what’s going on, you need to know some things about potatoes. Today, they’re one of the world’s most important crops. But what most North Americans know as a potato is a specific domesticated version of ancient taters that grew in the Andes. They were brought to Spain in the 1500s and to Britain a few centuries later, and slowly made their way into the European diet.
“Potatoes are really resilient,” says horticulturist Laura Shannon of the University of Minnesota. Because they were domesticated in the harsh environment of the Andes mountains, they are tough, she says—even though the reds, yellows, and russets many of us enjoy today are the result of hundreds of years of domestic breeding. “They’re not like bananas or oranges, which we’re worried about keeping around as a plant we’re going to eat,” says Shannon. “We’re going to keep eating potatoes.” In other words: calm down, your french fries are safe.
That said, this year was a really bad year for spuds, says agronomist Andy Robinson, who is part of North Dakota State University’s potato extension office.
It all started at the beginning of the growing season, he says. A long winter with snowstorms stretching into April delayed planting by about 10 days. Then harvest time brought its own tater troubles: “We had tremendous rainfall around the middle of September through October,” he says, “and a blizzard in the second week in October that put down upwards of two to three feet of snow in some of the potato growing areas.”
Wet weather made it impossible to get harvesting equipment out into the fields, he says. “Usually farmers will wait and hope that conditions improve. But the problem was that we just kept getting rainstorm after rainstorm, and then we got a blizzard in the middle.”
That problem isn’t confined to this year’s crop. “We are having increasingly unpredictable and weird weather events because the climate is changing,” Shannon says.
It also put the potatoes at greater risk of disease. Like other plants, potatoes have pores known as lenticels that allow them to “breath.” They generally appear as little spots or slits on the potato’s skin. But when the plants are exposed to lots of water, Robinson says, the lenticels open up much wider to get more oxygen. All of those open pores create a gateway for pathogens. Bacterial infection or mold might cause the spuds to die before harvest, or it might manifest later, when they’re stored, causing them to rot—and perhaps infect other potatoes nearby.
Shannon and her colleagues are working on developing more disease-resistant potatoes, but it’s always a slow effort, she notes. Developing a new cultivar can take more than 30 years, and even making small genetic tweaks can take around a decade, since potatoes have four sets of chromosomes (rather than the two that most animals and many plants have). Having that many genes in play just makes the whole process more complicated. Shannon and others are working on developing a simpler potato: to do that, they’ve gone back to the Andes and found a cultivar that naturally has two chromosomes rather than four. They’re trying to breed that trait into domesticated potatoes, she says, but it’ll take a while.
In the meantime, one of the reasons this year is noteworthy is because potato growers across North America all experienced a bad year at the same time. As a result of almost universally cruddy weather, Bloomberg reported, potato output in the US is expected to drop to its lowest since 2010, by 6.1 percent, and Canadian crops also saw significant losses.
Bad years are just part of agriculture, and farmers are prepared, says Robinson, even if a pan-North American year of dud spuds is unusual. For this year’s potato supply, “I don’t think there’s a large concern,” he says, because potatoes are a very global agricultural market and demand can likely be made up (at least for the most part) using imported crops.
Makers of french fries and other processed goods, who mostly use russets and who produce their frozen foods all year round, already have good potato stockpiles, says Robinson. They can likely make up any deficits next year by growing a quick crop somewhere warm, like Nebraska or Texas, he says.
Seed potatoes are what we should be worrying about. Tubers can produce clonally, meaning that if you cut up healthy potatoes, each chunk will grow into a copy of the starter spud. The seed potato crop is a specialized bunch specially cultivated to be free of disease. Only some states are licensed to grow seed potatoes, but all the potatoes grown in North America are grown using the resulting chunks. Since the continent-wide potato crop is smaller this year, that means the seed potato crop is smaller, too. That means a bad 2019 harvest will have an impact on crop yields in the years that follow.
“As far as a [potato] shortage, it potentially could happen for another year or two,” he says. His team and others are still trying to figure that out. But you probably don’t need to start hoarding frozen tots for a rainy day.
