Yamashita spinach has become an expensive commodity because of creator Asafumi Yamashita's thoughtful and careful farming practices. Yamashita, known as the "Japanese Vegetable Whisperer," grows this highly valued green along with turnips and other vegetables in France. Famous restaurateurs and Michelin-starred chefs are pretty much his only clientele, according to Food Republic. And Times Now reported that a bushel can go for about $13 per pound.

While hops give IPAs that "hoppiness" some people love, they can also be eaten like other green vegetables. I don't recommend eating them raw, though, due to their bitter flavor. Try sautéing them with a little oil and garlic.

Hops are pretty small, love growing in cold conditions, and tend to be rather challenging to harvest. Some specific varieties go for between $8 to $14 per pound. If you want to buy your own, Hops Growers of America has some great resources.

Le Bonnotte potatoes might be the most expensive tuber on the planet, coming in at a whopping $500 per pound, per Yahoo Finance. The dainty and aromatic potatoes grow in the Bay of Biscay, where farmers pick them by hand.

The area's algae, seaweed, and salty ocean water all contribute to the potato's flavor. They have a short season, so people buy these hot potatoes faster than you can say "hot potato!"

If you want to elevate your creamy mushroom pasta or veggie burgers, this one may interest you. Matsutake is a Japanese wild mushroom grows throughout Asia, Europe, and the United States. It has a spicy flavor and can be prepared like most other mushrooms. Its season lasts a third of the year, and according to the Los Angeles Times, they cost around $80 apiece. You can also buy them dried for a tad cheaper.

La Rosa del Veneto radicchio, known as pink lettuce or chicory, is a first-class leafy veg. Initially grown in Venice, Italy, you can also find it in the U.S. at Whole Foods or Eataly.

This lettuce has made its way to fine-dining restaurants, and is enjoyed in a lightly dressed salad. They are indeed pretty but have a bit of a bite—I can vouch for their delicate and somewhat bitter flavor. As the New York Post reported, Campo Rosso Farms in Pennsylvania sells pink lettuce for $10 per pound.

Some people refer to these salty, tear-drop-shaped peas as "green caviar." In Spain's Basque country, their season lasts through the spring, making them a hot commodity for chefs and local purveyors.

These peas should be hand-harvested and only cooked briefly. You'll see the peas in savory food but don't be surprised if you see it served with ice cream, too. The New York Times reports that these little guys can cost up to $100 per pound.