A salad with sweet crab, diced watermelon and raw corn is a winner on Sweetgreen’s always-seasonal menu. (Dixie D. Vereen/For The Washington Post)
Food critic

As big as Sweetgreen has grown in the 10 years since it rolled out in little more than 500 square feet in Georgetown, the health-minded, fast-casual, "full-scratch" recipe from a trio of college buddies has never strayed from its mission: Buy from local producers and be a good neighbor.

Nowhere is the idea played up more right now than at the latest and biggest branch of Sweetgreen in the District, where a sign on the sidewalk promotes "true blue" Maryland crab and the walls inside the city's 12th outlet include sketches of Georgetown and a white neon sign welcoming nearby students with "Hoya Saxa." (The chain, now based in Los Angeles, makes a habit of hiring customers who happen to be artists to enliven its stores.) What's more, from 9 a.m. to 1 p.m. on Saturdays, the adjoining parking lot hosts vendors from Freshfarm Dupont Circle Market, where co-creator Nicolas Jammet, a 2007 graduate of Georgetown University, met some of his original suppliers. His comrades are Jonathan Neman and Nathaniel Ru.

The Shroomami, top, and spicy crab and watermelon salad feature local ingredients and marry bold flavors with varied textures. (Dixie D. Vereen/For The Washington Post)

Genesis Torrez tops off bowls at the new Sweetgreen restaurant in Georgetown. (Dixie D. Vereen/For The Washington Post)

Early on a recent weekend, I found myself in a swiftly moving line, surveying what looked like the best part of the food pyramid: chopped peaches, sweet potatoes, red cabbage, chicken, sesame tofu and more. A menu on the wall tempted me with all sorts of appealing ways to combine some of those selections. Anyone who likes to eat to the tune of the season should gravitate to the combination of sweet crab, diced watermelon and raw corn while it lasts. Bulked up with romaine and mesclun, and spiked with a carrot-chile vinaigrette, the salad lets summer linger, at least on the palate. Heartier is the Shroomami, a warm mix of fleshy portobellos, shredded kale, wild rice, earthy beets (hold on, there's more), roasted tofu and sunflower seeds. A gingery miso dressing ties the elements together.

The pedigree of almost every ingredient is listed on a chalkboard. That kale in your chicken Caesar salad? Thank Richardson Farms in Maryland.

"Light, medium or heavy?" a counter server asks. She nodded to the dressings and I found another reason to bond with the homegrown chain, which expects to have more than 80 branches by year's end. "Light," by the way, gets you but a suggestion of your application of choice. "Medium" is more my style. Several squirts of spicy cashew dressing on a Rad Thai salad — organic greens tossed with crisp bean sprouts, springy shrimp and shredded carrots and cabbage — kept the contents of my bowl restoring rather than nap-inducing.

Speed is critical for Sweetgreen’s co-creators, and by eliminating cash at District branches, employees can move customers through the line quicker — especially during busy lunchtime hours. (Dixie D. Vereen/For The Washington Post)

Not all drinks are created equal. Cucumber juice with lime and ginger slipped some cool in a hot day, but watermelon fresca with cilantro tasted watered down.

Sweetgreen, which prepares all its food on site and offers online ordering, is cashless everywhere except Boston. A sign at the counter calls it a win-win policy for all involved, since more guests can be served in less time when no one has to count money.

"We're big believers in constant evolution," says Jammet, a trailblazer in the industry.

Ten years is a long time for restaurants and for revolutions — and Sweetgreen excels at both.

1044 Wisconsin Ave. NW, 202-838-4300. sweetgreen.com. Salads and warm bowls, $6.60 to $12.65.