<p>The activity with the greatest participation among the inhabitants of Havana’s urban communities related to biodiversity is the management of domestic gardens. Home gardens are species-rich socioecological systems with the potential to contribute to sustainable food, biodiversity, and responses to the climate crisis. This research aimed to assess the diversity, composition, and distribution of domestic garden plants, and to identify conserved indigenous species in a heavily urbanized city. In the municipality Regla within Havana (Cuba), a total of 66 gardens were randomly selected, visited, and inventoried in 2020. Cultivated plant species were identified and counted, and their frequencies and abundance were calculated. Plant species richness, Shannon diversity, evenness, and Simpson diversity were determined. A total of 338 species were recorded, grouped into 84 families and 227 genera. The flora of the gardens in Loma Modelo is mostly native (~ 55%), with components from the domestication centers of Mesoamerica (97 spp.), South America (50 spp.), and Africa (50 spp.), mainly. Eleven uses were identified for the plant species, with ornamental, religious, and medicinal ones being the most common. The number of species per garden varied widely, from only five to as many as 77, with diversity indices confirming this marked disparity. Considering the uses, Regla’s home gardens can be defined as mostly ornamental, with aromatic plants in almost all of them. This may be related to the fact that 92% of the gardens are managed by women, confirming the social character of domestic gardens. These results highlight the role of domestic gardens as reservoirs of plant diversity and cultural practices in urban areas, and their potential to contribute to sustainable urban development.</p>