The effect of CuO NPs on the germination and growth of Lactuca sativa and Solanum lycopersicum revealed significant benefits at the initial stage of seedling development. Soaking the seeds in a 25 mg/L solution of CuO NPs accelerated germination, with a 2.26-fold increase in the germination speed index (GVI) of tomato seeds and a 40% higher germination rate on the first day for lettuce seeds compared to the control. In addition, the application of NPs promoted superior root and shoot growth, indicating a promising potential for their use in agriculture.