Gardening was the act of caring for plants. One who did this professionally was called a gardener.
According to Jadzia Dax, none of the former hosts of the Trill symbiont Dax were good at gardening. Tobin Dax was the only one who tried, only to fail miserably. (DS9: "The Wire")
As she had grown up around farmers, Kathryn Janeway's parents insisted that she and her sister, Phoebe, learn basic gardening skills, something she hated at the time but found satisfying as of 2372. (VOY: "Resolutions")
Gardening was one of the activities that the Daystrom Institute promoted for the rehabilitation of sentient computers incarcerated in their Self-Aware Megalomaniacal Computer Storage. Peanut Hamper and AGIMUS often tended to the plants together during their time there. (LD: "A Few Badgeys More")