Although Blake Christiana has limited experience with the needle and spoon (he admits he tried heroin once at age 16), he doesn’t hesitate to weave junky romance into his lonely acoustic tales, like losing the girl when she finds him prepping his vein in the new song “I Wanted to get High.” It’s not uncommon for barrooms full of fans to chime in, singing, “Throw away my money/Throw away my friends/Throw away my future on a cold bag of sin/When I wanted to get high.” Few actually process that the sing-along lyrics are not about a bag of green stuff.

“I like to make it as dark as possible,” says Christiana. “Some songs are straight from experience. Others are just exaggerated yarns, as they say. But I definitely don’t have a heroin problem.”

Truth be told, he’d be hard-pressed to balance a dope habit with the demands of an increasingly popular touring band. The song-driven Americana group’s third release, 2010’s Come on In, was built on the following gained from 2008’s Empty Pockets. Empty Pockets made a splash partially thanks to guest appearances by Tony Trischka, Casey Dreissen, Edie Brickell, and Caitlin Cary of Whiskeytown.

Fortunately, Christiana is endearing enough that he can e-mail Paul Simon’s wife (Brickell) and soon thereafter find her singing harmony beside him. He and his bandmates — mandolinist Andrew Hendryx, bassist Rick Bugel, drummer Robert Bonhomme, and guitarists Trevor MacArthur and Rod Hohl — have built relationships around Charleston and Folly Beach.

A YouTube video on their site (search: “Yarn Folly Daze”) chronicles the four days they spent on Folly last winter, canceling tour stops in Florida in favor of staying put, playing impromptu shows at the Drop In Deli and Surf Bar, and drinking heavily, much to the delight of locals.

“I want to get stranded on Folly again,” laughs Christiana, recalling that in a sober moment, the band opted to leave under the cover of night before getting caught for another day. “Y’all know how to do it,” he says. “I love it down there.”

This time around, Yarn’s stop at the Pour House doesn’t leave time for a Folly jaunt. They return in support of Leftovers, Volume 1, a collection of unreleased tracks recorded during sessions for their first two albums. Christiana anticipates a second volume in the fall.

In the meantime, he’s been busy writing new material, including a slew of seven tunes penned in one week in May. It’s part of what he calls the “morning songs experiment” (available on the band’s website). Christiana announced that every morning after waking, he’d compose and complete a song before moving on to the rest of his day, releasing a video recording immediately on the site. The results are impressive, reaching from the utter despair of forlorn loneliness (“My Wasted Life”) to a highway song titled about bandits rushing for the Mexico border ahead of the cops (“One More Mile”).

“By day two, I was like, ‘Fuck this,’ but it was funny because certain days felt really good and easy,” recalls Christiana. “We’re already playing six of those tunes with the band. A couple of them have some balls live.”

On one struggling morning, Christiana penned a tune called “Thank You for Coming Round.” It managed to strike a chord of true American folk ever more difficult to find in his New York hometown. While he sang, low and slow over quiet guitar chords, an American flag rested on the couch beside him, and a siren passed outside his Brooklyn apartment window.

“That’s my blankey,” explains Christiana, surprised by the observation. “I guess it just happened to be crumpled up there. I had just gotten up.”

Christiana says he’s often explaining to reporters that his brand of country-ish folk songwriting isn’t faking a Southern style, but continuing a New York tradition that’s mostly been forgotten.

That may be so, but Christiana has fallen victim to at least one incomparable perk of the South these days, spending most of his time off from touring with his girlfriend in Raleigh, N.C.

“There ain’t nothing better than a Southern girl,” laughs the Yankee convert. “Especially one with a real country accent.”