Urban agriculture (UA) initiatives have become a key area of research, policymaking and activism in reaction to the dominance of global for-profit supply chains that have introduced significant food-related vulnerabilities in urban areas. However, empirical evidence shows that UA initiatives encounter powerful implementation barriers imposed by the neoliberal powers that have established such supply chains. This article proposes that ‘neo-austerity urbanism’ has become a relevant political strategy that supports such barriers. It considers the case of Lisbon and is informed by an interview-based inquiry aimed at identifying the implementation barriers blocking the development of transformative UA initiatives in this city while making such initiatives an integral part of neo-austerity urbanism. Three types of barriers were identified: those derived from the envisioned urban realm; the governance system in place; and the urban agriculture model envisioned. Together, these barriers form an effective mechanism to suppress urban agriculture as an activity with transformative potential in social, environmental and economic terms.