Mixtures of plant extracts and silver nanoparticles, as alternative disinfectant agents during in vitro plant propagation, reduce contamination and production costs. This study evaluated the in vitro antiseptic effect of silver nanoparticles (AgNPs) and the plant extracts obtained from Hibiscus sabdariffa (Roselle) calyces, Allium sativum (Garlic), and Cinnamomum verum (Cinnamon). Twelve mixtures were prepared at different concentrations but only two showed antiseptic effect greater than 70%. Dendrobium nobile was used as a plant model and twin jars temporary immersion bioreactors, with four 1-min immersions every six hours. The combination in culture medium of 13% roselle extract, 0.6% cinnamon extract, 7% garlic extract, and 0.1% silver nanoparticles showed the best results, increasing the multiplication rate by 22% (5.4 shoots), the number of leaves by 7% compared to the control without plant extracts. Our results suggest that plant extracts combined with silver nanoparticles could be used as a viable technical and economical option in the mass micropropagation of D. nobile.