She made her Carnegie Hall debut in April 2007 at a tribute to Neil Sedaka.In 2008, De Garmo was set to star alongside Tony Award nominee Gavin Creel in the Broadway revival of Godspell at the Ethel Barrymore Theatre, but on August 19, it was announced that the show was postponed indefinitely due to the loss of an investor.

At age ten she was part of the Cartoon Gang on The Cartoon Network, appearing in various bumper segments.

As a third grader she was a Coca-Cola Kid during the 1996 Summer Olympics in Atlanta, Georgia.

De Garmo began recording a pop/R&B album in 2007; After filming CMT's Gone Country in late 2007, she relocated to Nashville.

She signed to John Rich's production company and recorded material with him in 2008.

The songs were never released and De Garmo moved on to other collaborators.

In February 2009 she self-released a four-song acoustic country EP, Unplugged in Nashville, to digital retailers.

After producing a music video for "Good Goodbye," fans were asked to vote on two versions of the video on the American Idol website. De Garmo made her major stage debut as Maria in an American Musical Theatre of San Jose production of West Side Story in November 2005.

She followed with her Broadway debut in a four-month run of Hairspray as nerdy Penny Pingleton taking over for Tracy Miller in February 2006.

Diana De Garmo was born in Birmingham, Alabama, but was raised primarily in Snellville, Georgia.