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Lobelia erinus has characteristics that are ideal for use in urban landscaping, including cover applications in vertical gardens and greenroofs. In these systems, it is necessary to optimize water usage and irrigation management in order to ensure the survival of plant cover. Incorporating a nutrient solution recirculation mechanism or alternative water resources into the vertical greenery system and green roofs design would make it possible to install this type of system in Mediterranean arid and semiarid areas. However, wastewater and recirculated water resources are also characterized by a higher salinity than fresh water. We evaluated the effects of salinity in a hydroponic system with nutrient solution recirculation in Lobelia, characterizing ion concentration content in plant tissues and ornamental characteristics, we aimed to determine proper plant selection for use in vertical garden and green roofs. Complete nutrient solutions were supplemented with 6, 30 and 50 mM NaCl, yielding final electrical conductivities of 2.0, 4.5 and 6.5 dS m(-1). Increasing salinity affected plant growth, causing reductions in biomass, plant height and diameter, and increased shoot to root ratios. Salinity increases had no effect on flower production, and it did not produce toxicity symptoms on leaves despite significant accumulation of Na+ and Cl- in these tissues. These results highlight the salinity tolerance of Lobelia erinus, and its potential utilization for urban landscape uses exposed to salinity or irrigated with poor-quality waters.