Credit: Photos by Darrow Montgomery

The thickening mist has the college-age kids in the Merriweather Post Pavilion parking lot worried.

“Is there an umbrella in there?” says a bare-shouldered concertgoer. She’s sitting on the ground, wrapped in a blanket. “We’ve got two,” chirps her friend, who’s still optimistically wearing sunglasses.

It’s 1:30 p.m., and the tailgaters don’t appear to be in any hurry to get into the Sweetlife Festival, where U.S. Royalty is currently playing the big stage. The real draws, they say, are the acts scheduled for later this afternoon: Crystal Castles, Girl Talk, and, of course, The Strokes.

“The beer in there is $9, so you want get a buzz going out here first,” explains the bare-shouldered fan.

Sweetgreen founders Nathaniel Ru, Nic Jammet, and Jonathan Neman.(Photo by Darrow Montgomery)

Inside, though, the organizers have other refreshments on tap—plenty of them available for free. On a ridge behind the lawn seats, a pair of affable guys dispenses Honest Tea while pitching fans on the beverage’s health benefits. Nearby, concertgoers queue up for samples of Stonyfield Farms Greek yogurt. Many of them may have already gotten a taste of the Lara Bars and Pirate’s Booty being handed out by representatives of MOM’s Organic Market. In the same tent, a face painter is busily decorating a long line of young faces: Options include recycling icons, wind turbines, and, of course, MOM’s logos.

“We’ve been in line for an hour,” says a 19-year-old kid named Tosin, tightening his hoodie around his unpainted face. It’s beginning to rain.

Still, even the unhappy music fans have something to be glad about. Somewhere in the face-painting line, a concertgoer expresses displeasure with how far his $40 seats are from the stage. “This is a soggy rip-off,” he declares. And then, a second later: “Let’s get more yogurt.”

There’s also plenty of promotion going on in a fenced-off VIP area. Here, a fetching young bartender is serving up samples of yet another Honest Tea product, a new cacao-bean brew called “CocaNova.” “It’s got all the antioxidants of chocolate,” she explains.

Meanwhile, a scruffy guy offers passersby a chance to try on silly hats—while sampling Popchips, a fluffy, low-fat potato chip.

As summertime festival concerts go, Sweetlife is pretty ordinary. As a marketing exercise, on the other hand, it’s brilliant.

Especially when you consider that its namesake and main organizer—the outfit that stands to benefit from associating with rock stars and the coveted youth demographic—is a 4-year-old salad chain with a measly nine stores to its name. Sure, BlackBerry may be bankrolling U2’s current tour, and T-Mobile might be bringing you the Blink-182 reunion, but Sweetgreen, founded in 2007 by a trio of 21-year-olds, employs a few hundred people, as compared to the tens of thousands working for the telecom giants. With that sort of size, it seems downright miraculous to see Gregg Gillis, aka Girl Talk, trot out on stage in his sweatband and hoodie to shout, “Hello, Sweetlife Festival!”

(Photo by Darrow Montgomery)

For the guys who started Sweetgreen, the rock show is no happy accident. Rather, it’s part of their grand plan—a plan that says a lot about how we buy food and how we think about music these days. Like the other brands seeking to establish themselves by handing out freebies of natural ice tea, Sweetgreen’s founders are using their cultural sponsorship to woo a generation of consumers. Only instead of hiring promo folks in nice T-shirts, they hired The Strokes.

Sweetgreen’s founding legend is a compelling one. Jonathan Neman, Nic Jammet, and Nathaniel Ru, all Georgetown University business majors, say they couldn’t find anywhere to eat near campus that was both healthy and inexpensive. So they started an eatery themselves, opening up shop in a Lilliputian M Street NW space opposite the apartment Neman shared with Ru.

(Photo by Darrow Montgomery)

Like any inspiring story, Sweetgreen’s involves overcoming some hurdles. The tiny store didn’t have plumbing or electricity; its owner didn’t want to rent it to neophytes. But the guys, having decided to forego the investment banking jobs that many of their classmates had snagged, were determined. “I called every day for weeks,” Neman says. Opening up just ahead of the salad-and-tart-yogurt trends, they’ve since expanded to nine restaurants in three states and the District. Regularly logging 15-hour days, they plan to open eight more locations in the next year.

Of course, there are some details that don’t quite fit into that narrative. For one thing, the guys say their favorite restaurant during their undergrad days was José Andrés’ Café Atlántico—hardly an example of cheap eats for starving students. It also leaves out their parents.

(Photo by Darrow Montgomery)

“We all come from families that are entrepreneurs, and I think we all value that innovative, entrepreneurial spirit,” says Neman, a smallish guy with a tall, asymmetrical haircut. “We’re all first-generation immigrants, too.”

The immigrant roots, though, are not of the scrappy, bootstraps-pulling variety. Neman’s family, which fled Iran in 1979, runs a multi-million dollar textile business. Ru’s father, an immigrant from Taiwan, had a successful import-export concern that traded in “promotional items,” like magnets and stickers. And Jammet’s parents, Swiss and French, owned La Caravelle, the midtown Manhattan restaurant where Kennedys and Rockefellers regularly dined.

Family connections helped the trio raise start-up funds from investors including Joe Bastianich, the business partner of celebrity chef Mario Batali. Peter Hapstak, the architect behind Brasserie Beck and dozens of other hip D.C. restaurants, won awards for his eco-friendly design of Sweetgreen’s first store.

The three raised significant money to start the business, but they didn’t spend much on marketing. They didn’t need to—the story of three young guys starting a sustainable salad store was too delicious to pass up. Zagats, Fast Casual, and other food-industry organs wrote about Sweetgreen before it even opened. A month later, The Washington Post ran a glowing review, singing the praises of the chain’s Guacamole Greens salad and frozen yogurt: “Sweetgreen’s team has already delivered on its promise of fast, healthful food to go.” Business at Sweetgreen’s Georgetown location spiked.

In the restaurant business, success can be elusive—even for the well-connected. In March 2009, Sweetgreen opened its second store just off Dupont Circle with an additional $780,000 from private investors. The Great Recession was in full swing. Customers were scarce.

(Photo by Darrow Montgomery)

“The only thing we could think of was attracting people through music,” says Ru, a tall guy who wears his hair a bit shaggier than the average young-enterpriser type. So Ru and Neman walked down Connecticut Avenue to The Guitar Shop and bought a $300 amp. They plugged in Neman’s iPod and queued up some Daft Punk. It wasn’t a good fit. “Due to the older crowd around that day, [it was] not getting a good reaction,” Neman says.

So they switched to mainstream indie rock, working in oldies like “Son of a Preacher Man,” too. It turned out to be a perfect salad-eating soundtrack. “It attracted people,” says Ru. “It made people say, ‘Maybe this is more than just a salad place.’”

Starting with that amp, Sweetgreen began producing successively larger music events. U.S. Royalty and Matthew Hemerlein played store openings and block parties. In January, they rang in the New Year with Rob Myers, of Thievery Corporation, at their Reston store. Toro y Moi, a critically acclaimed electropop artist, serenaded lunch crowds at the Logan Circle store in April, and Walk the Moon and The Givers played in-store sets this month.

Last summer, Sweetgreen threw its first multi-band event in the parking lot next to their Dupont Circle store. And this year, the Sweetlife Festival upgraded to Merriweather, one of the region’s largest music venues, with a capacity of nearly 20,000 people.

(Photo by Darrow Montgomery)

“I remember I was at [Neman’s] house when he brought up the idea they wanted to do a festival and get The Strokes,” says Jacob Michael, the bassist for U.S. Royalty. “I thought he was crazy; I thought he was out of his mind.”

Booking one of the most influential rock bands in recent memory was an ambitious goal, but it turned out to be rather do-able, even for a comparatively puny business. The total cost of the 10 bands at the festival, according to booking estimates, could easily have totaled $350,000. But where Neman, Ru, and Jammet’s hipster-networking moxy came into play was convincing some of their suppliers, including Stonyfield, Honest Tea, and Applegate Farms, to help foot the bill.

It was a pretty appealing offer: For a chunk of their marketing budget, the firms got to position themselves on the cool side of American culture. Sweetlife filled out the lineup with ostensibly up-and-coming musicians, including mash-up artist Girl Talk, electro-screamers Crystal Castles, and rapper Lupe Fiasco. “We made bets on people who are going to get bigger,” Neman says. “We want Sweetlife to be the first place people saw them.”

Of course, the groups had one other thing in common: None of them was all that edgy. The guys had learned the lesson of the amp very well.

Getting into music is a smart move for a fledgling brand like Sweetgreen, says Rajeev Batra, a business professor at the University of Michigan. “People identify very deeply with their musical choices,” Batra says. “If a brand is able to link itself to a musical event, style, or performer, they can connect deeply with consumers, potentially building greater engagement and emotional loyalty.”

All the same, the scrappy, state-school crowd at the Sweetlife Festival isn’t the same one you see at a Sweetgreen store. The typical lunch crowd at Sweetgreen’s Dupont store, for instance, seems to consist mostly of professional women, age 25 to 35. There’s a reason Gnarls Barkley is on the store soundtrack, and Crystal Castles are out at the festival. But then again, appealing to the younger rock-show types, marketing folks say, can still win you some cultural legitimacy in the eyes of the $9 salad set.

“A music festival with hip bands is going to contribute to a brand’s image,” Batra says.

In some ways, the income and age gulf between the Sweetlife Festival crowd and Sweetgreen’s customer base was a mistake, says Neman. When deciding the lineup, the three went through their iPods and chose their favorite bands, he says. “I think Girl Talk brought a young crowd,” says Neman. “We didn’t realize it when were booking it so much.”

But like many Sweetgreen mistakes, it was probably a lucky one. It doesn’t matter that many Sweetgreen customers have never heard of Lupe Fiasco—they sense he is cool, and eating at a restaurant that books him makes them feel a little cooler themselves.

It’s the Sweetgreen sweet spot: A young, hip image, and an older, richer clientele.

In the long run, Neman says, he wants that sweet spot to expand beyond salads—with to-be-determined new goods and services filling the space. In an interview, he throws around lingo that even the best-compensated rock festival performer would never talk about onstage: “Sweetlife is the lifestyle surrounding Sweetgreen,” he says. “We’d like to get into fitness, apparel, anything that falls under a healthy, balanced, and fun lifestyle.” The festival, he says, was just the best way to introduce the world to that lifestyle. The Strokes may have helped sell yogurt this summer, but they could be selling yoga pants within a few years.

Batra, though, says extending a brand into new industries can be tricky. For example, Clorox’s attempt to launch a detergent brand fell flat, perhaps because consumers worried it would bleach out their clothes. Brands with more generic associations diversify more easily. Names like Ralph Lauren or Martha Stewart can be applied to clothes, paints, dishes—almost anything, Batra says.

“Lifestyle brands aren’t locking themselves into one niche,” he says. “They can go wherever the business is.”

Which is good news for the Sweetgreen guys, because you’d be hard pressed to think of a term more pliant than “Sweetlife.”

“The Sweetlife is whatever you want it to be,” Neman says.

Sweetgreen headquarters, just north of Dupont Circle, does a pretty good impression of a Silicon Valley startup, circa just before the tech bubble burst. A ping-pong table stands in for a conference table. A nearby whiteboard records win-loss records for the dozen or so central office staffers. Over the historic fireplace is a large flat-screen TV attached to a MacBook. On display: The seasonal salad for June, a green beans and goat cheese number. Like every MacBook in the office, this one has a Sweetgreen sticker over the glowing apple.

Scattered around the room, for no apparent reason, are musical instruments: a dingy white Yamaha keyboard, a turntable, two guitars. On a windowsill, there’s stack of Nintendo Wii games.

On a Thursday morning last month, Jammet, a short guy with a shaved head who uses the word “sweet” with alarming frequency, is sitting at the ping-pong table chatting with Andrea Northup, the coordinator of D.C. Farm to School, a local nonprofit that brings local food to school cafeterias. Northup has about a foot on Jammet, who is the only Sweetgreen founder who looks old enough to own a multi-million-dollar business.

“Do you wear that shirt everyday?” asks Northup, pointing to Jammet’s Sweetgreen T-shirt, which he’s layered underneath a button-down work shirt. “Pretty much,” says Jammet, good-naturedly. In fact, Neman and Ru wear the same outfit nearly every day, too. They also sport Converse sneakers and silicon Sweetgreen bracelets, “Livestrong”-style.

Today, Northup has come to Sweetgreen to help Jammet plan the “Sweetgreen in the Schools” program, which teaches kids about healthy eating. “Can our staff and interns have VIP free salad cards?” she asks, and then tacks on a request for a metal Sweetgreen canteen. Jammet happily hands over the canteen and promises to look into the free salad cards.

Northup and Jammet get down to the business of planning out the program. Among the class activities the salad chain will sponsor: “Eat the Rainbow,” which will get children brainstorming names of fruits and vegetables and then writing them on a color wheel. An intern scribbles notes in a Sweetgreen Moleskin-style notebook.

A discussion ensues about where to run the summer-school curriculum; Northup suggests working with a school that already has a strong healthy-eating program. Jammet, however, says he wants a challenge. “Let’s pick out a high-needs school,” he says. In the end, they pick Brookland Education Campus and Anacostia’s Savoy Elementary School. In the meantime, Jammet suggests giving out coupons for free salads and then sending the Sweetflow mobile truck to the school. That way, the kids would take their salads home—where parents would presumably be inspired to make delicious salads of their own. According to Northup, parents often send their children to her farm and ask them to bring home mustard greens, but they never seem to want lettuce or tomatoes. “It’s like they don’t know what to do with it,” she says.

“They have never had a delicious salad,” Jammet adds.

As the meeting wraps up, Northup asks Jammet for her organization’s check from the Sweetlife Festival. A portion of the proceeds will go to D.C. Farm to School as well as the Jamie Oliver Foundation, which has a similar mission. Sweetgreen wouldn’t disclose how much they’d raised. “Sorry, we haven’t closed the books yet,” Jammet says. “We are still decompressing.”

Neman, Jammet, and Ru don’t look like they need to decompress. The three 26-year-olds are fit, tan, and confident, and they all exude a laid-back intensity that you rarely see outside of Owen Wilson movies. They also comprise a mix of ethnicities that would be the envy of a Benetton ad. But if you close your eyes, they’re hard to tell apart. All three speak with lazy surfer vowels and employ MBA phrases like “brand halo.”

In addition to co-owning a business, Ru and Neman share a house near the 9:30 Club; city property records say the modern rowhouse was purchased last December for $919,000 by Ru, Neman, and Neman’s brother. Jammet lives across the street. Sometimes they commute to work together, Neman on an eco-friendly bamboo skateboard, Ru on his fixed-gear Sweetgreen bike, and Jammet on his Peugeot. The hectic work schedules make other relationships tricky, Jammet says: “Sweetgreen is our significant other.”

After the meeting about getting salad to poor kids, the rest of a day with that significant other involves a TV interview (Neman had to shush the prep cooks as he did an in-store interview with WRC-TV’s Wendy Rieger; on camera, he extols the deliciousness of his store’s salads), a welcome-aboard meal with a new crop of interns (the interns get their own versions of that silicon Sweetgreen bracelet), and some time for instructing interns on how to run the corporate Twitter and Facebook feeds (one intern’s winning post idea: “Knowledge is knowing the tomato is a fruit. Wisdom is knowing not to put the tomato in the fruit salad.”).

Late in the day, they have a more serious meeting, with marketing consultant Charlie Jones. Cue the MBA-speak: “You guys, at your most dangerous, market to yourselves,” Jones says. “You should be asking yourself about broader appeal, designing an experience for somebody else.”

It’s a message they’ve heard before. “They are selling a product that’s more expensive than the typical lunch, and they are up against much larger, better funded, huge restaurants and corporations,” says Seth Goldman, the president of Honest Tea and a Sweetgreen investor. Goldman says the business is at a point where expansion is going to get a lot trickier.

On the other hand, do you think of The Strokes when you pass a Chop’t storefront? Didn’t think so.

Back at Merriweather, the farmers market is limping along as The Strokes take the stage. It’s been this way all day: Long lines at the generic burrito cart, not much action at the tent serving Sweetgreen’s own salad. Maybe it’s not so easy to convert people to the sweet life—or at least the part of it that involves eating quinoa salad while rocking.

“We heard the salad line was long in the beginning of the day,” Jammet says later. “Maybe people, later in the day, got drunker and started wanting burritos.”

With the monotone vocals of “Is This It” saturating the air, the guy manning the produce stand seems vexed by piles of unsold strawberries. He offers me two cartons for $4, then quickly drops the price to $1 each. “Come on,” he says. “My bosses are here. Don’t make me look bad.”

The link between hip music and sustainable food, admits Ru, may not be quite as obvious to others as it is to Sweetgreen’s founders. “Next year, we are going to make sure it’s not just a Strokes concert or a big party, but make sure it connects back to the idea of natural, sustainable food,” he says. Still, the concert was a success, with 90 percent of tickets selling, and a total attendance of about 15,000.

And for all the culinary pretensions, it’s easy to see how large portions of those 15,000 people could walk away with a different message. For instance, inside the gates, there’s almost as much stress on marketing something you can’t eat: smartphone apps. A live Twitter feed on a large screen encourages festivalgoers to post some 9,000 #sweetlife tweets. It ultimately overloads nearby AT&T towers. The message is not food, but Sweetlife itself. “To some extent, I’m glad we overloaded the towers,” says Peter Corbett, CEO of iStrategyLabs, the company contracted by Sweetgreen to “be the social experience agency for the festival.”

Together, the two companies social-market the hell out of Sweetlife. In addition to the now-standard Facebook page and Twitter feeds, the festival has three official smartphone apps. Over the course of the afternoon, somewhere between 500 and 1,000 Sweetlife attendees install Color, a photo social-networking app, on their iPhones, using it to play a massive game of iSpy—taking photos of, for instance, “someone living the Sweetlife,” or “the sweetest smile.” The first three people to answer win VIP bracelets, giving them access to a side-stage area with unlimited Popchips and a shortcut to the front of the pavilion. Corbett later tells me that more people used the app to take pictures of the festival than April’s royal wedding.

Only time will tell how Sweetgreen’s founders will capitalize on their festival’s brilliant tribe-building and social marketing. But one thing is clear: They have more on their agendas than simply promoting sustainable food.

“Over time, this whole region and probably the whole country will know about Sweetgreen and Sweetlife,” Goldman says. It’s hard not to agree: After nine hours at the show, I realize I haven’t gone 30 seconds all day without seeing one of those two words.

“Next year, we’re going even bigger,” Neman says.