Abstract: In order to explore the suitable mixed sowing method of thyme in garden crops,the effects of different concentrations of thyme extract on germination rate,germination potential,root length,bud length,conductivity and MDA content of Calendula officinalis and Viola tricolor seeds were studied by hydroponics.The results showed that when the concentration of thyme extract increased,the germination rate and germination potential of Calendula officinalis and Viola tricolor decreased gradually,and the root length and bud length increased first and then decreased.The treatment of 0.1 g·mL^-1 extract was significantly lower than that of the control group.The relative conductivity and MDA of the two seeds increased with the increase of the concentration of the extract.The low concentration of thyme extract has little effect on seed germination of Calendula officinalis and Viola tricolor,and high concentration of thyme extract can inhibit seed germination and seedling growth of Calendula officinalis and Viola tricolor.