Input subsidies are the single greatest expenditure under poverty reduction programs in Zambia. Yet maize yields continue to fall well short of international standards. One major reason appears to be the yield limiting effects of acidity, which is highly common on Zambian soils. We suggest a diversification of the input subsidy scheme beyond fertilizer to include inputs that reduce acidity and raise the yield response to fertilizer application. We further discuss specific recommendations for diversifying productivity investments to put more emphasis on extension and agronomic research.