Spatial and informational effects and psychological pathways in forage adoption-stage progression in erosion-prone Ethiopian highlands

• Neighbors’ stages were strongly linked to forage adoption-stage progression. • Attitude was strongest among constructs; perceived behavioral control was next. • Subjective norm mediated interpersonal information via attitude and control. • Mobile/radio access mattered most in the decision-to-implementation transition. • Shorter distance to the agricultural office operated indirectly via agent access. Under intensified land pressure, land degradation threatens land productivity and environmental quality in the Ethiopian highlands, yet voluntary uptake of sustainable land management practices remains uneven. Adoption is a staged process in which information exposure and peer networks shape psychological shifts that translate intentions into action. This study examines how spatial dependence, information channels, and Theory of Planned Behavior (TPB) constructs drive adoption-stage progression in forage planting, which provides fodder incentives and soil improvement. We surveyed 202 smallholder households, classified five adoption stages, and employed structural equation modeling (SEM) and a spatial autoregressive ordered probit (SAROP) model with 1-km spatial weights. In SAROP, neighbors’ adoption stages showed the strongest association with stage progression (ρ = 0.368). Attitude was the largest psychological predictor (β = 0.348), followed by perceived behavioral control (PBC; β = 0.163). Mobile-phone ownership (β = 0.185) and radio access (β = 0.168) were also positive. SEM indicated that subjective norm operated indirectly, bridging interpersonal information to attitude and PBC (total indirect β = 0.156), and distance to the agricultural office affected stages via access to development agents and TPB constructs (total β = -0.125). Transition analyses suggested that TPB constructs and interpersonal information matter most early, whereas mobile/radio access is most salient in the decision-to-implementation transition. Results suggest policy can support spatially targeted, stage-specific extension combining peer facilitation with mass-media channels to enhance perceived feasibility and benefits. Overall, this integrated spatial–informational–psychological approach is transferable to other smallholder contexts, supporting farmer-centered, stepwise strategies to promote adoption.