Ahead of Valentine’s Day, MIT economist Jonathan Gruber joined Boston Public Radio on Thursday to explain why rose prices have skyrocketed — and why most roses in the United States are now shipped in from South America.

Although the U.S. rose industry once utilized large, heated greenhouses to cultivate roses year-round, the United States began importing roses from South American countries — particularly Colombia and Ecuador — due to their warmer climates.

During a recent trip through South America, Gruber and his wife visited rose farms in Ecuador and Colombia that produced approximately 60,000 roses a day. Buying a dozen roses in person from rose farms in Colombia and Ecuador, he said, costs about $1.20.

But in the United States, that cost is, on average, $12 — a 22% increase from last year’s price. That price jump reflects a floral shortage stemming from layoffs and farm closures during the first few months of the pandemic, as well as current supply chain issues issues.

“As consumers of roses, we feel good: roses are a lot cheaper than they [should] be,” Gruber said. “Roses are expensive, but they're a lot less expensive than they would be if we had grown them in the U.S.”

The rising rose prices come as the United States is hitting its highest rate of inflation in 40 years, as the Labor Department announced Thursday.

“In the U.S., you know, inflation-adjusted terms, roses aren't actually that much more expensive to give than they were when I was young,” Gruber continued. “On the other hand, a lot of people [who] used to work in these heated greenhouses have lost their jobs. This is really a Valentine's Day microcosm of the larger debate over international trade.”