Throughout the 1970s and 1980s, agricultural production in Cuba was characterized by high use of external inputs: chemical fertilizers, pesticides, mechanization and fuel. As a result, millions of hectares of soil degraded and compacted. The content of organic matter decreased, and pH values of soils increased affecting certain crops such as vegetables, tubers and rice. Due to the economic downturn affecting Cuba and the continuous decreasing support from socialist countries in Europe since 1990, the use of chemical fertilizers and other inputs has sharply decreased by 20-25% from the consumption levels observed in the 1980s. This decline negatively affected agricultural productivity, providing Cuban scientists with a unique opportunity to play a protagonist role in the search for more effective and efficient ways of using traditional agricultural inputs (zeolite and Cuban rock phosphate employ included) as well as other national alternative sources such as organic and green manures, vermicompost, and a wide variety of biofertilizers. The combination of lower levels of inputs and other alternative sources together with the introduction of new forms of production, allow today Cuban farmers to obtain higher average yields than those obtained during the 1990s. In the framework of the organic production, the successful movement of Urban Agriculture was also considered. The paper concludes that under Cuban conditions in particular (and Latin America in general), sustainable agriculture is possible only by incorporating an Integrated Crop Nutrition Management approach. This approach is based on a) the diversification of the agricultural production in a determined area allowing crop rotation, and b) the management of all nutrient sources (including chemical fertilizers) and water in order to optimize the efficiency of nutrients supply to the different crops. The paper also shows an example of this approach.

Key words: crop nutrition management, chemical fertilizers, nutrients alternative sources