This paper presents a historical overview of plant breeding research, variety release and seed supply of staple food grains in Zimbabwe, and assesses the impacts of the new varieties on yields using national aggregate yield data. The paper also analyses farm-level factors determining farmers’ adoption decisions in the semi-arid areas, where the mini-green revolution lagged behind more favorable areas. The results indicate that the adoption of improved crop varieties will not lead to substantial yield gains unless improved soil management methods, such as application of manure and fertilizer, are also adopted..