When the nights grow long, holiday magic gets strong and there’s no place better suited for it than the Saenger Theater (6 S. Joachim St.). The grand dame of Mobile showplaces gets her most fantastic makeover of the year when the Mobile Symphony Orchestra (MSO) convenes for its December concert.

For yuletide spectacle, MSO turned to a reliable source: Ron Barrett. Known for his fanciful decorative work in all phases of Mobile Carnival season, Barrett let his imagination roam in service to MSO.

“With Ron, more is more,” J.C. Barker laughed. As MSO’s general manager and director of artistic administration, he conferred with Barrett on décor for months.

They used Barrett last year for the first time and were pleased with the spectacular results. Barker ran down a recently received list.

“Nine painted distant snow trees; 20 white glittering snowflakes with ivory cords; three foliage trees with light, each with glittered pine cones; six lighted balcony trees; 3,000 bright red ornaments; foliage swirls across the front of the stage with red ornaments and glittered pine cones, clear lights,” he recited in awe.

All that’s missing are lords a-leaping, partridges and pear trees. Of course, Santa will be in the lobby.

No wonder it’s going to take Barrett multiple days for set-up. The lobby gets the first treatment, with décor going up in early December but everything for the stage and theater itself is for MSO only.

“He’ll come in on the day before we get in there [for rehearsals on Dec. 12],” Barker said. “He’ll continue to set up on Dec. 13 so three days just to install our stuff.”

Two shows follow, a 7:30 p.m. concert on Dec. 15 and a 2:30 p.m. matinee on Sunday, Dec. 16. For those farther north, MSO will travel to Monroeville Thursday, Dec. 14 for a free concert at the Nettles Auditorium at Alabama Coastal Community College. While last year’s version was inspired by popular mid-20th century orchestrations of contemporary origin, MSO is going back to classical fare in 2018.

“We’ve done a lot of different things, traditional Christmas, Christmas carols, Santa Clauses and this time we just wanted to concentrate on doing something really beautiful. So we looked at the best, most beautiful Christmas stuff out there,” Barker said.

That list includes numbers many Americans don’t automatically summon when pressed for seasonly tunes like Max Reger’s “Maria Wiegenlied,” Pietro Yon’s “Gesu Bambino,” Hugo Wolf’s “Schlafendes Jesuskind”and Léo Delibes’ “Flower duet from ‘Lakmé.’” The vocals needed for those numbers feature a pair of guest sopranos.

“Martha Guth is going to be with us and also Clara Osowski who is a mezzo [soprano] and they’re both really brilliant, smart singers. We’re excited about it,” Barker said.

According to her website bio, Guth has appeared with the Toronto Symphony Orchestra, the Santa Fe Symphony, the Canadian Opera Company Orchestra, the National Arts Centre Orchestra and the Calgary Philharmonic. She won first prize at the 2007 Wigmore Hall International Song Competition in London and was recorded live by the BBC in London, CBC radio /radio Canada and CBC Television.

Osowski was a 2012 Metropolitan Opera National Council Upper-Midwest Regional Finalist, a winner of the 2014 Bel Canto Chorus Regional Artists Competition in Milwaukee and runner-up of the 2016 Schubert Club Bruce P. Carlson Scholarship Competition. In 2017, she won the Houston Saengerbund Competition.

The remaining program — “Ave Maria,” “O Holy Night,” “I Wonder As I Wander,” Nigel Hess’ “Christmas Overture,”  John Rutter’s “Candlelight Carol,” — is familiar.

They’ve taken a different tack with Tchaikovsky’s practically requisite “Nutcracker.” Rather than the typical individual character dances, MSO will perform the Waltz of the Snowflakes and Act One Finale along with its grand pas de deux. Still, it’s accessible.

“The show might look more esoteric than it really is. All the tunes are short. It’s a Christmas concert,” Barker said.

There’s even a nod to last year with three Carmen Dragon arrangements of traditional carols.

The most sizable feature is likely the appearance of the Eastern Shore Choral Society. With 100 members, they’ll be tucked into any available space onstage.

“They are going to be on four of the numbers with us and the big finale. The orchestra isn’t as big as Mahler but it’s still a regular-size orchestra,” Barker said.

Barker is confident for good reason. He was still proud of something from a September rehearsal with Renee Fleming.

“Right after we read the first [Strauss song] with her, she turned around to the orchestra and said, ‘That is absolutely the finest reading I have ever had with any orchestra.’ Trust me, she didn’t have to say that,” Barker said.