Applying lime to agricultural soils can provide a range of economic, production and environmental benefits for the farmer and the wider agriculture sector. ‘Ag Climatise’, the national climate and air roadmap for the agriculture sector in Ireland, published in 2020 highlights the need for Ireland to apply two million tonnes of lime per annum if we are to reach our environmental targets. Over the past number of decades Ireland has failed to continually surpass one million tonnes of lime applied annually. Therefore, despite the obvious benefits, Irish farmers are not applying the appropriate amounts of lime to their farms. This study applied mental models as the conceptual framework to analyse this problem. The insights and opinions of influential stakeholders including suppliers, researchers, policy makers and extension specialists on issues with lime application were collected and analysed. Their views were combined into a singular ‘expert’ mental model that would represent the perspective of the wider AKIS. The expert model was then compared and contrasted against that of actual farmers to determine whether they aligned and whether the ’experts’ were fully aware of the drivers and barriers affecting farmers every day practices. The analysis of the mental models revealed similar perspectives held by the experts and farmers around issues with extension services, lime marketing and farmer attitudes and motivation. However the experts focused more on areas such as soil testing and research whereas farmers had keen interest in the practical implications of lime application as well as the significance of farmer’s habits and values. The study points to the need to address the issues preventing greater adoption of lime by farmers with particular attention to issues identified from the farmer mental model, including those factors likely to have a significant influence on farmers’ attitudes, beliefs and practices. Recommendations to strengthen current advisory approaches include the development of localised strategies that will address the key needs and realities a specific region may be encountering. A localised participatory model could empower advisors together with local supplier and other vested stakeholders to provide targeted bespoke information to farmers in ways that would improve engagement and encourage increases in lime application.