Formulation of fertilization plan is important task in agricultural production, but frequently performed by advisors without necessary information about individual plots and fertilisation practices applied by individual farmers. With increasing concerns for environment and sustainable production it is therefore important that fertilization planning is done by farmers. High fertilizers' prices also urge to their rational application, achievable only on the basis of plans for several years. In the article an electronic tool for fertilization plan formulation is presented. It is developed as a multi-criteria decision making model based on mathematical programming techniques. Hypothetical case illustrates its application as well as strengths and weaknesses of methodology applied.