The aim was to obtain Japanese iris varieties with different flowering periods, original colour of flowers, good corrugation of petals and greater resistance to various adverse environmental factors in the south of Primorsky Krai, Russia. New varieties were created by spontaneous and directed hybridization of geographically distant varieties, selection of adaptability donors and involvement of radiation mutagenesis in the breeding process. Intervarietal hybrids were characterised by intermediate inheritance of colour and flower shape, generative and vegetative productivity, plant height and flowering time. The inclusion of hybrid forms in the breeding process allowed the variety of flower colour and shape, flowering time and generative productivity to be expanded in the F2 generation. Promising interhybrid forms with biological characteristics that determine the possibility of their cultivation under the extreme conditions of the subregion were selected. A hybrid fund was created: over 135 adapted genotypes and 14 varieties. On the basis of the long-term experimental research, the expediency and necessity of breeding work with Japanese irises under the conditions of the subregion was established.