Of Gardner's first one-man show at the Collective Gallery in Edinburgh in 1986, Edward Gage, art critic from The Scotsman newspaper, wrote, “Using a variety of media and technical effects, creating mood with color and movement with line and texture, this unusual artist creates emotive visual poems from figurative and abstract elements that tell a private tale or symbolize a state of mind.”
In 1993, Gardner exhibited paintings at the Abney Gallery and Limner Gallery, New York. Sean Simon of Art Speak wrote, “A sense of cosmic mystery comes across in the work of Scottish artist Paul Gardner. Employing vibrant colors, mixing geometric and organic forms, Gardner creates canvases that are a testament of faith in the act of painting itself.”
Gardner was featured in COAST Magazine's September 2009 issue, in which art critic and writer Roberta Carasso stated, "With his European training, Gardner moves the image beyond traditional landscape to reveal the endless wonders the earth manifests: its three-dimensional forms, colors, textures, and amazing configurations."