Gardner was born in Gloucester, and sang as a chorister at Gloucester Cathedral. As a youth, he played piano, clarinet and organ. He attended the King's School, Gloucester and Eton College. At the University of Cambridge, he continued as a music student, and was a choral scholar in King's College Choir. He had begun choral conducting at Eton, and continued conducting at Cambridge. He also studied at the Royal Academy of Music, where his teachers included Colin Metters. He graduated from the RAM in 2000. From 1997 until 2002, Gardner was Musical Director of Wokingham Choral Society, a post previously held by Graeme Jenkins, Paul Daniel, and Stephen Layton. In 1999, whilst still a student at the Royal Academy of Music, Gardner became a repetiteur at the Salzburg Festival at the invitation of Michael Gielen, when another repetiteur had become ill. Gardner subsequently served as an assistant conductor to Mark Elder at The Hallé Orchestra for 3 years. In 2003, Gardner was named music director of Glyndebourne on Tour, and held the post from 2004 to 2007. In 2005, Gardner was a winner of the Young Artist prize of the Royal Philharmonic Society. In March 2006, he was appointed music director of English National Opera. He formally took up the post in May 2007, with an initial contract of 3 years. Although there had not been any formal press announcements of Gardner extending his ENO contract, he publicly stated in 2011 his plans to work with ENO until at least 2015. In January 2014, ENO announced the scheduled conclusion of Gardner's tenure as music director in 2015. In September 2010, the City of Birmingham Symphony Orchestra announced the appointment of Gardner as its next principal guest conductor, effective September 2011, with an initial contract of 3 years, for 3–4 weeks of concerts per season. He concluded his tenure as CBSO principal guest conductor in July 2016. Outside the UK, in February 2013, Gardner was simultaneously named the next principal guest conductor of the Bergen Philharmonic Orchestra, effective August 2013, and the orchestra's next principal conductor effective with the 2015–2016 season. His initial contract as principal conductor was for 3 years. In January 2017, the orchestra announced the extension of Gardner's contract in Bergen through 2021. In September 2019, the orchestra further extended Gardner's Bergen contract through 2023. Gardner had made his guest-conducting debut with the London Philharmonic Orchestra in 2003. In July 2019, the LPO announced the appointment of Gardner as its next principal conductor, effective with the 2021-2022 season, with an initial contract of 5 years. Gardner has conducted several recordings for EMI Classics, including collaborations with Alison Balsom and Kate Royal. He has also signed a recording contract with Chandos Records, which has included recordings of music by Witold Lutosławski and Benjamin Britten.
