The interspecific hybrids were obtained in three crossing combinations of Cuphea viscosissima Jacq. and Cuphea lanceolata Ait. The F1 hybrid plants were planted in the field and during the growing season the following was performed: morphological description, biometric measurements and phenological observations. Intermediate inheritance phenotypic parameters were foundwith the help of the morphological description. On the degree of dominance of quantitative traits in F1 hybrids ranged from negative to positive overdominance. Im all hybrid combinations there was identified the somatic heterosis, in reproductive traits heterosis manifested itself in the parameter weight of 1000 seeds