Gardiner has played on the PGA Tour of Australasia and its developmental tour, the Von Nida Tour, where he won once (Queensland PGA Championship 2005). He played on the European Tour from 2001 to 2003. He played on the Nationwide Tour from 2003 to 2012, where he won the 2010 Chattanooga Classic. After the 2012 season, he graduated to the PGA Tour and made his Tour debut at the 2013 Sony Open in Hawaii. He made only seven cuts in 23 events and finished 177th on both the money list and the FedEx Cup that year. He played the Web.com Tour Finals, finishing in eighth place to retain his PGA Tor card for 2014.
- Gardiner is the first person of Aboriginal descent to earn a PGA Tour card.
- Never travels without his thongs (flip-flops)First car was a Mitsubishi Colt.
- Kingston Heath is his favourite course and would like to play Augusta National.
- Was a competitive discus thrower when he was younger.