Water is involved in ensuring the life of plants. It participates in the formation of the internal structure and appearance of the plant [1-5]. One of the purposes of xylem is transport nutrients from the soil through the roots to other plant organs. The main aim of the present paper is to formulate a model for the rise of an aqueous solution of salts (as nutrients for the plant) in the xylem and to analyze changes in the movement of the solution in depending on various parameters. The approach gives a possibility to take into account changes of parameters in space and time, as well as the non-linearity of the considered processes.