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Optimizing a three-way pact comprising crop yields, fertility inputs and greenhouse gases may minimize the contribution of croplands to global warming. Fluxes of N₂O, CO₂ and CH₄ from soil were measured under maize (Zea mays L.) grown using 0, 60 and 120 kg N hm^-2 as NH₄NO₃-N and composted manure-N in three seasons on clay (Chromic luvisol) and sandy loam (Haplic lixisol) soils in Zimbabwe. The fluxes were measured using the static chamber methodology involving gas chromatography for ample air analysis. Over an average of 122 days we estimated emissions of 0.1 to 0.5 kg N₂O-N hm⁻², 711 to 1574 kg CO₂-C hm⁻² and−2.6 to 5.8 kg CH₄-C hm⁻² from six treatments during season II with the highest fluxes. The posed hypothesis that composted manure-N may be better placed as a mitigation option against soil emissions of GHG than mineral fertilizer-N was largely supported by N₂O …