The alien flora of Montenegro is enlarged by 5 new species: Coreopsis tinctoria, Ipomoea indica, Lupinus × regalis, Physalis angulata, and Solidago canadensis. All species are grown as ornamentals, and thus horticulture is considered the most possible pathway for their introduction. Nevertheless, in the case of Physalis angulata, the occurrence might have originated in the remains of picnic meals. In order to define the alien status of these species, monitoring is needed, and thus we propose including the species on the National List of Indicators in environmental protection. Special attention should be paid to the species with invasive potentials: Solidago canadensis, Ipomoea indica and Physalis angulata.