Alternative approaches to resolve bottlenecks in food production often champion the reuse of urban organic waste as fertiliser in agriculture in order to close the nutrient cycle between city and country (cradle to cradle). References are often made to the past because environmental historians tend to work the use of urban wastes into a story of environmental symbiosis between city and countryside. This article argues, however, that closed nutrient cycles did not exist even in pre-industrial society, as the way in which agriculture was structured had a huge impact on the demand for manure. Starting from two agricultural regions in eighteenth-century Flanders, this research calls for more attention to regional structures of agriculture in which cities were embedded and to how these agro-systems shaped nutrient flows from the city to the country by very diverse patterns of demand for fertilisers, leading to unequal redistributive flows of nutrients from towns to different agricultural regions.