During 2011–2023 in the south of Western Siberia, with the aim of introducing and selecting a new species of clarkia (C. purpurea), its biological characteristics and morphological characteristics were studied. Based on the data obtained and the use of other species and varieties of the genus Clarkia Pursh. For the first time, a methodology for conducting tests for distinctiveness, uniformity and stability (DUS) for this crop was developed. This technique is applicable to all varieties of the genus Clarkia Pursh, classified into sections: Godetia (C. purpurea (Curtis) A. Nelson & J. F. Macbr.), Phaeostoma (C. unguiculata Lindl.), Rhodanthos (C. amoena (Lehm.) A . Nelson & J. F. Macbr., Clarkia amoena ssp. lindleyi (Douglas) H. F. Lewis & M. Е. Lewis), fireweed family (Onagraceae Juss.). Many species of clarkia are characterized by long-lasting flowering and are promising for floral decoration of urban spaces, as well as for cutting. Most varieties are from very low – up to 25 cm tall, to very high – 96 cm or more; leaves are simple, lanceolate, narrow-lanceolate, wide-lanceolate, ovate, smooth, pubescent. The flowers are very decorative, varying in size from 2.0 to 8.0 cm tall, simple, semidouble, terry and strongly terry with or without fragrance, with a large variability of colors and types of floral pigmentation. Based on the study of the bioecological and morphological properties of the crop under study and in accordance with the rules approved by the Federal State Budgetary Institution “State Varietal Commission”, 36 characteristics were selected by which it is possible to test clarkey varieties. As a result of breeding work, a new variety of C. purpurea, Lilac Fairy, was created. When analyzing crossing, it was established that the lilac (violet) color of flowers is dominant in relation to pale pink (almost white), and when crossing F1 hybrids with light purple color, splitting 15:1 (15 violet from dark purple to pale purple was obtained and 1 is pale pink), which confirms the hypothesis about the polygenic nature of the inheritance of the main color of flowers in C. purpurea. The national methodology RTG/1157/1, created for the first time, for testing the DUS of Clarkia Pursh varieties will serve as a scientific basis for practical breeding.