The humble, wise, and ancient act of planting tomatoes by those who obstinately take care of a void left over by urban sprawl is an ambitious and noble act contesting the multiple manifestations of injustice. It is a claim about the place people want to live in and the society people want to be part of. In recent years, urban gardening has become a practice which responds to many needs as it can promote a sense of community stimulating social cohesion; it strengthens urban ecosystems by increasing urban biodiversity and fighting climate change; it is a way of experimenting models of innovative production and management of public spaces, mitigating spatial and environmental injustice. The impacts are generally affecting positively on social, economic, environmental, political aspects of urban life, as for the challenges, there are still many since it is not easy to find the right balance between spontaneous and institutionalized initiatives.