The paper describes the results of a three-year study of biological characteristics of ‘Malika’, ‘Professor Parolek’, ‘Dolgozhdannyy Debut’ gladiolus cultivars on the territory of the Education and Research Center «Botanical Garden» in Saratov State University (Saratov) and the Genkel Botanical Garden in Perm State University (Perm). Plants in Saratov region experienced a detrimental effect of high summer temperatures and insufficient humidity: the height of the plant and the size of the inflorescence, the number of flowers in the inflorescence decreased. Nevertheless, the gladiolus development rate matched the biological characteristics of the cultivars in the Saratov Botanical Garden, they happened to go through the growing season before the frost and formed a mature replacement corm. In the Perm Botanical Garden, the studied cultivars also went through all the stages of growth and development, but the flowering period of the studied cultivars started later, which may be associated with a decrease in summer temperature below the optimum temperature in some years. This may have impeded the maturation of replacement corms and increased the susceptibility to fungal diseases. At the same time, the studied gladiolus cultivars retained most fully their decorative features in the Perm Botanical Garden.