“It just didn’t seem possible,” admitted South Florida Symphony Artistic Director Sebrina Maria Alfonso about her orchestra’s collaboration this week with principal dancers from the legendary Martha Graham Dance Company.

The symphony’s program, “Spring Is In the Air,” featuring Aaron Copland’s masterpiece of classical Americana, “Appalachian Spring,” had already been scheduled when a friend, Maurizio Nardi, a principal dancer with the dance company, suggested the music be performed as a ballet, as it was originally conceived.

“We jumped on it,” said Alfonso.

Most music fans are familiar with the orchestral suite arranged by Copland in 1945, but the lilting tunes were originally music for a ballet choreographed by Graham and performed by a small ensemble of 13 musicians.

“Even though it’s similar to the suite, the ballet was written for dancers and its missing a few measures here and there, just enough to be annoying,” explained Alfonso.

The symphony and three dancers will perform selected vignettes from the ballet first, along with readings from the many letters Graham wrote to Copland outlining her storyline and expectations for the work. Local actress and philanthropist Beth Holland will read the letters, which offer great insight into the creative processes of both artists.

“It’s quite wonderful,” said Holland. “In these marvelous letters, she eloquently explained her vision for the piece and then he would write it. They never dreamed it would be so successful. They never knew what they had.”

Graham frequently quoted the words of American philosophers, including Henry David Thoreau, in her directions to Copland.

“She wanted (Appalachian Spring) to be really American,” added Holland. “The real deal.”

Set in 19th century rural Pennsylvania, the ballet chronicles the activities of American pioneers, including a bride, groom, preacher, congregation and townspeople, and is organized into eight scenes or musical movements.

While the most famous is a set of majestic variations on the Shaker hymn tune, “Simple Gifts,” concert audiences will also get a chance to hear movements that Copland did not include in his suite, including a folksy revival featuring an energetic preacher. After the readings and dance performance, Alfonso will conduct the full symphony in the complete 22-minute orchestral suite.

The collaboration “just seems appropriate and matches what we’re doing,” said Alfonso. “I’m very excited this is coming about.”

In keeping with the “spring” theme, the program will also include the New York Philharmonic’s principal cellist, Carter Brey, performing William Schumann’s poetic Cello Concerto, and the remarkable Symphony No. 4 by Johannes Brahms.

The South Florida Symphony performs “Spring is in the Air” on Saturday, April 2 at the Tennessee Williams Theatre in Key West; Sunday, April 3 at the Kaye Auditorium on the campus of Florida Atlantic University in Boca Raton; and Tuesday, April 5 at the Broward Center in Fort Lauderdale. For tickets and more information, go to SouthFloridaSymphony.org.