Conservation Agriculture (CA) has been promoted during the last 15¿years in Madagascar to develop a sustainable rainfed agriculture in order to cope with low fertility upland soils, soil erosion, low productivity and erratic rainfall. If CA does provide a better sustainability with adapted cropping patterns when adopted, a question is, whether CA is able to alleviate the impact of climatic variations thanks to the mulching effect and to which extent. We took the example of medium altitude zones in the Lake Alaotra area to illustrate farmers' perceptions. If climate change is not proven in these areas, climatic variations are very high and erratic rainfall patterns at the beginning of the rainy season induce serious risks of crop failure. Two surveys were implemented in 2013: (i) on CA changing practices of 92¿farmers (during the 10¿years project duration) and (ii) on the evolution of behavior among 28¿farmers who have recently adopted CA (less than 5¿years). In CA systems, the mulch contributes to better cropping systems resilience and helps alleviating the effect of climatic variations. If a limited number of farmers have effectively adopted CA practices, in the long run, most farmers have developed innovative cropping systems between conventional agriculture and CA, to address their own constraints, leading to a widespread range of agro-ecological practices. A typology of behavior is presented to identify farmers' strategies regarding risks in a context characterized by multiple uncertainties.