Smallholder farmers across rural landscapes remain trapped in a vicious cycle of endemic poverty where interconnected challenges limit their ability to improve their livelihoods. Our study of smallholder farmers’ relationships with suppliers and several stakeholders across the Tanzanian rural agro-input supply chain offers an extended perspective on the persistence of endemic poverty and broadens the discussion on the future of sustainable food production and smallholder livelihoods. Through interviews and focus groups, we use a grounded theory methodology to develop a systemic approach to understanding the complexities of this landscape as related to smallholder agro-input sourcing activities. Our causal loop diagram framework provides a unique perspective on the poverty trap experienced by smallholder farmers in this context. Our findings may be useful in targeting practical and sustainable directions towards overcoming the poverty trap, ultimately enabling smallholders to increase wealth and improve their livelihoods through sustainable practices.