Cities, states, and countries across the globe are recognizing the interconnections of human and planetary health, and are investing in greening. Nevertheless, environmental improvements may not bring adequate changes in exposure needed to reduce chronic disease and improve mental health. Nature prescription, in which a health provider refers a patient to spend time outdoors, is a potential behavioral intervention that could connect people to accessible green spaces. However, formidable patient barriers could reduce the potential to scale-up implementation in equitable and sustained ways. We surveyed 2625 adult respondents within Australia, India, Singapore, the United States, and the United States about their perceptions of a set of seven potential barriers to participation in nature prescriptions. Analyses revealed that respondents in India and Singapore, although most aware of and experienced with nature prescriptions, reported facing greater barriers than in other countries. Weather was the most commonly reported barrier, followed by the lack of time and distance. A lack of interest was a greater barrier among young, urban respondents with a college degree. The barrier of the lack of company was greater for urban residents and for those experiencing financial difficulty. In addition, contrary to many prior studies, we observed greater overall perceived barriers for respondents with higher education levels. Many of the perceived barriers covered by our survey are structurally modifiable, and programs developing in each of these locations may draw from these findings to tailor outreach strategies.