Homegardens are vital traditional agroecosystems that provide year-round food and livelihood security for smallholder farmers, particularly in the tropics and subtropics. In southwestern Uganda, where they form the primary source of nutrition for rural marginalized communities, these systems are increasingly threatened by national agricultural policies, socio-economic pressures, and environmental degradation. Despite their importance, the ecological and social dynamics underpinning homegarden diversity remain poorly understood. This study aimed to uncover the structural and functional patterns of floristic diversity in homegardens and identify key influencing factors. A mixed-methods approach, grounded in a human ecology framework, was employed to analyze 102 randomly selected homegardens across a deforestation gradient in three districts of southwestern Uganda. A total of 209 cultivated crop species were recorded (mean 26.8 per garden), with food crops comprising 96% of individuals and 44% of species. Gardens near forest edges exhibited greater species diversity than those in deforested zones or near degraded wetlands. Multiple regression analyses identified elevation, location, garden size, market proximity, land ownership, and livestock as significant predictors of crop diversity. Cluster analysis revealed four distinct homegarden types, differentiated by species composition and structure, with classification accuracy of 98%. These findings highlight the adaptive nature of traditional homegardening practices and their responsiveness to ecological and socio-economic factors. The study underscores the role of homegardens as critical components of rural resilience and sustainable development, advocating for policy measures that support their conservation and integration into broader food security and land use planning initiatives in Uganda.