BOSTON - There's more green at Fenway Park than the infield or the monster wall.

The Red Sox are growing vegetables and herbs in a rooftop garden. The produce is used in food and cocktails sold at the concessions, at nearby restaurants and in the team's flagship restaurant that prepares meals for about 40,000 people during home games.

The 5,000-square-foot garden on the third-base side of Fenway has turned a previously unused part of the historic stadium into the largest of a handful of farms that have sprouted up in Major League Baseball stadiums, said Chris Knight, manager of facilities services and planning for the Red Sox.

The sight of a lush, green garden on the third level of the stadium excited Sox fan John Bunker, who recently travelled from his home in Palermo, Maine, to see the team in action and make a pilgrimage to the rooftop farm.

"This is great because although a lot of people love to come to Fenway and eat a hot dog, some people don't want to eat a hot dog, they want to eat something else - maybe a salad or a wrap with vegetables in it," Bunker said.

The garden is unique because the crops are grown in milk crates, which make it possible to move the farm if needed, said Jessie Banhazl, whose company, Green City Growers, is responsible for planting and maintaining the garden.

Growers use intensive methods, including drip irrigation and planting fresh crops right after others are harvested. That's enabled the garden to yield more than 2,000 pounds of tomatoes, cucumber, eggplants, all sorts of peppers, rosemary, basil, dill, parsley, tarragon and kale in the first three months, Banhazl said.

"So we're growing a little bit of everything," she said. "It's our first year doing the farm and so we thought we'd try out a bunch of different varieties to see what the kitchens were using, and also to just kind of experiment with what people liked."

Starting a farm at the iconic ballpark required checking the structural integrity of the roof and using lightweight soil, Banhazl said.

Growing crops atop a stadium packed with screaming fans can be distracting. Some, surprised to see a garden on the roof, wander over to ask questions.

"But we actually really enjoy that part of it. Being able to engage with the public is a huge reason why we do what we do," she said.

Determining what's grown involves consultations with chefs at the Red Sox flagship EMC Club restaurant.

"I've been here since 2006 and along with that came that farm-to-table mentality," said Ron Abell, senior executive chef at Fenway concessionaire Aramark, who oversees food preparations at the restaurant.

"For years we've been using all the local farmers - you know, kind of creating our dishes with what's in season and making sure that food doesn't travel too far to get to us," he said. "Well, it's ridiculous how close it is now because literally it's about 150 feet from us."

"A lot of folks come to Fenway Park and maybe it's a day they're eating our delicious hot dogs and sausages and pizza and chicken tenders," Abell said. "But there are still thousands of people looking for something healthy, and it's just great to be able to give them that opportunity to go eat healthy at the ballpark if that's what they want to do."