This paper illustrates a mathematical model describing growth and development of the potato crop LINTUL-POTATO. The model is used firstly to identify suitable potato growing areas and seasons anywhere in the world through agro-ecological zonation. Then the model allows the identification of the genetic requirements of potato crops to achieve the highest yields in the identified zones and seasons through the exercise of ideotyping. The degree of adaptation of existing cultivars and new genotypes is examined through exploration. Special adaptations of LINTUL-POTATO are used in decision support for planning of e.g. applications of water and nitrogen. The model is used for quality monitoring (e.g. dry matter concentration and tuber size), yield prediction and scenario studies. The methods involved are explained and examples of the various applications are given.