Due to increased awareness of the current and future issues with the environment, sustainable development has become a well-known concept and goal in the last decades. Based on this idea, organic agriculture is now fairly generalized in many farms and grape processing factories. Life cycle assessment (LCA) represents a valuable and standardized technique to evaluate how sustainable a crop can become, determining the potential impacts that the complete-life product causes on the environment and on the management/conservation of resources. Although LCA can be applied to any product, this work focusses on organic grapevine crops as the subject of study, in order to improve energy and water efficiency and minimizing issues such as the use of pesticides. This paper, collecting primary data from three Spanish grape processing factories, quantifies the reduction of the overall impact related to the avoidance of artificial irrigation, amounting to 10%, and the saving of resources (− 4.3 kg oil eq. per ha) due to the replacement of chemical fertilisers with animal manure. On the other hand, the use of manure has shown some controversy from an environmental point of view as it contributes to global warming, resulting in an increase in the total impact of the organic vineyard. As predictable, the application of conventional practices as well as the use of water for irrigation could both result in a higher overall yield, and in a contemporary growth of environmental impacts; a discussion about the quantification of this aspect is also inserted.