The day potato farmers in San Luis Valley had been waiting on for more than 25 years finally came as Mexico’s decades-long limitation on Colorado-grown potatoes came to an end earlier this month. 

Since 1996, Mexico has limited the export of U.S.-grown potatoes to just within 16 miles of the U.S.-Mexico border, fearing pest and disease problem.

That all changed on May 11, when the first shipment of Idaho-grown potatoes that went into Mexico’s interior crossed the border.

That change is the result of a late 2021 agreement and a more recent one, signed in April, between the two countries. The agreement, according to a May 12 news release from the U.S. Department of Agriculture, means U.S. potato exports to Mexico could more than quadruple over the next five years. 

Currently, about 10% of Colorado potatoes, grown primarily in the San Luis Valley, are exported to Mexico. In 2021, that was about 122 million pounds, according to a news release Monday from Gov. Jared Polis. Mexico is the top export market for all U.S.-grown potatoes, according to the National Potato Council and Colorado potatoes represent nearly half of all potato exports into Mexico. 

“Colorado is strategically positioned to lead the nation in potato exports to Mexico providing new revenue for Colorado potato farmers,” Polis said.

More than 70 potato varieties are grown in the San Luis Valley. 

Potato exports from Colorado and the rest of the United States have been hampered by several factors: concerns about disease and pests, negotiations over the U.S. Mexico-Canada-Agreement (USMCA) trade deal and litigation by Mexican farmers.

The disease and pest issue is tied to what’s known as the golden nematode, a type of roundworm that attaches itself to roots of potato and tomato plants. An outbreak can wipe out an entire crop, according to the U.S. Department of Agriculture’s National Invasive Species Information Center. 

The plant parasite is common on both sides of the border, and controlled by fungicides and other means.

The second problem is Potato Virus Y, aka PVY, which is spread by aphids. In 2010, to address that issue, Colorado implemented a potato seed act that required potato growers to use certified seed potatoes at least every other year. That act was most recently renewed in 2019. 

Next came negotiations, first over the North American Free Trade Agreement and later, the USMCA. Both opened up Mexico to U.S. potatoes, but potato imports were never implemented because Mexico’s version of the National Potato Council filed a lawsuit against the government in 2014, claiming the government had no authority to decide whether agricultural exports were legal. A 2017 lower court ruled in favor of the farmers.

A major milestone in that litigation took place a year ago, when the Mexican Supreme Court ruled 5-0 that the government did, in fact, have that authority.

That led to the April site visit to Mexico City by Commissioner Tom Vilsack of the U.S. Department of Agriculture to finalize arrangements on a number of issues, including potato exports.

But the degree to which the new agreement benefits the San Luis Valley remains a big question mark, in large part because of drought.

James Ehrlich, executive director of the Colorado Potato Administrative Committee, said that after years of drought, continuing into this year, farmers are “not going to be able to increase our production capability.”

The Upper Rio Grande River basin, which feeds the San Luis Valley, is in extreme drought. Winter snowmelt in the basin peaked three weeks ahead of normal, meaning drought conditions are not likely to improve anytime soon.

Ehrlich, however, added that potato exports to a wider Mexican market represent a “huge opportunity, with 70 million new customers that we didn’t have before.”

But he added potato growers are greeting the news with a little skepticism, given that a similar lift on the limitation took place several years ago and closed shut after just six weeks.

Prices are also a consideration, Ehrlich said. If a potato shipper can get a better price shipping to Mexico and can deal with the hassle of crossing the border, then that’s where they’ll go. He added that the first load of Colorado potatoes to go beyond the 26 kilometer limit hit Mexican grocery stores just this week.