Spoleto Festival USA goes out on a French note — not the highfalutin variety of French, but rather the swampy, zydeco kind.

Four-time Grammy nominee Cedric Watson and his band, Bijou Creole, bring the sounds of Louisiana to Middleton Place for the festival finale Sunday. Get ready to dance on the plantation lawn, as Watson sings blues-influenced lyrics while alternating between fiddle and accordion.

Watson grew up in small-town Texas but gravitated toward traditional zydeco and old-school Creole music. Still in his late 20s, he makes Louisiana French music modern and relevant.

His gig at Spoleto’s festival finale continues a tradition of down-home roots music. Last year, the Del McCoury Band brought bluegrass to the plantation lawn, and in 2010 the Carolina Chocolate Drops introduced old-time, African-American string music to the captivated crowd.

Gates at Middleton Place open Sunday at 3:30 p.m., and music runs all afternoon. Spoleto marketing director Paula Edwards said the added entertainment gives festival-goers a good reason to venture 15 miles out of the city for the finale.

“It’s a fantastic afternoon to begin with,” Edwards said. “We felt like we needed to animate the afternoon a little bit.”

Charleston-based Americana band, The Local Honeys, kick off the tunes at 4:15 p.m. when they take their homey blend — which includes ukulele and glockenspiel — onto the stage.

Another Charleston favorite, the Royal Tinfoil, takes over at 5:15 p.m. The self-described “drunken gypsy sex or soulful, drug-laced Americana” brings a quirky, hip-swinging blend of country and rock.

Valerie June, bearer of distinctive long dreadlocks and purveyor of “organic moonshine roots music,” begins her set at 6:15 p.m. Her gravelly sweet voice recently earned her some ink in The New Yorker Magazine, which dubbed her locks “the most amazing hair in New York.”

Finally, after that long cast of characters, Watson and Bijou Creole will play the main stage at 8:30 p.m.

This year’s festival finale includes a beer garden with draft beers from local Palmetto Brewing Company and fried chicken and barbecue from Middleton Place. As always, the fun continues after the bands finish with a festival-ending fireworks display.

Reach Allyson Bird at 937-5594 or Twitter.com/allyson jbird.