This study aims to describe staff experiences of nature as a tool for working with people with mental illnesses. A qualitative study consisting of nine interviews with staff working with nature as a tool was conducted. The data were analysed using qualitative content analysis. Two themes with six subthemes emerged. The first theme, making the invisible visible with subthemes, getting in touch with nature, getting in touch with feelings and acceptance of time and lack of demands, and the second theme, working with what we have with subthemes, nature becomes a tool for resiliency, the surrounding environment becomes a safe setting and important relationships for good treatment. The healthcare staffs' experiences of incorporating nature as a caring tool for patients with mental illness showed that nature could contribute to a patient's recovery. For psychiatric nursing, this study observed that having the knowledge and awareness of nature's effect on patients, and using it as complementary care and treatment-tool may inspire both staff, and their patients to further include nature-assisted care and therapy in their treatment of mental illnesses on the road to improved mental health.