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The growth of urban forests located in dry lands depends on the availability of irrigation water. This is a scarce but vital resource for forestry development and for the sustainability of the corresponding urban model. This paper evaluates the water stress effect on the most frequent tree species of Mendoza’s Metropolitan Area (Platanus hispanica, Morus alba and Fraxinus americana). The main objective is to evaluate the growth responses and propose management strategies and urban design guidelines to ensure the permanence of the urban forestry in the city. An experimental essay was designed based on the application of differential irrigation (control, moderate and severe water deficit) to young tree specimens through three growing seasons. Tree water consumption and the growth responses (heigth, diameter and leaf area) were evaluated. Data indicate a greater impact of water deficit on M. alba and an increased water demand for P. hispanica, with significantly higher average requirements (3.15 to 2.10 cm(3).dia/dm(2)) with respect to the other tree-species. F americana was the species with the most favorable conditions to achieve proper growth with bounded water inputs allowing a rational use of the resource. However, in the selection of tree-species, this approach must be consistent with the conditions imposed by the cities on the vegetation and the characteristics of the urban scenarios to be planted.