Water management for rainfed maize in semi-arid Zimbabwe

Mulch ripping and 1.0 m tied ridging (furrow diking) are viable options for improving maize yields in semi-arid smallholder farming systems but the two conservation tillage methods face resource constraints. Deep-rooting (≥ 0.60 m effective rooting depth) maize cultivars at a final plant density of 44400 plants ha-1 can produce  7.8 t ha-1 maize grain yield under conventional tillage (ploughing using an ox-drawn  mouldboard plough and planting on the flat). Farmers will benefit more from practices that reduce soil evaporation e.g. mulching; practices that improve effective rooting depth e.g. deep ploughing and deep ripping. Furthermore, farmers should be encouraged to add organic fertilizers to improve soils’ available water capacity and enhance response to mineral fertilizers. A combination of large field-edge and small in-field rainwater management technologies is required for sustainable rainwater and soil management in semi-arid smallholder farming systems of Zimbabwe.