Aims: Amendment of ferralitic soils of Ngaoundere (Cameroon) by rock materials, so-called petrofertilizer, can be a promising solution to improve their fertility and thus enhance crop yield. Study Design: In the present study, the influence of pyroclastic powder on the growth of the common bean (Phaseolus vulgaris L.) was assessed. Place and Duration of Study: Department of Biological Sciences. The sowing was done on June 13, 2017 until 2 septembre. Methodology: An experimental design with four (04) different treatments was implemented: 0 g per pot (0% of pyroclastic: the control), 150 g per pot (10% of pyroclastic: P10 Treatment), 300 g per pot (20% of pyroclastic: P20 Treatment) and 450 g per pot (30% of pyroclastic: P30 Treatment). The pyroclastic powder was applied at three different (03) stages: sowing, germination, and flowering stage. All the treatments were irrigated with 250 ml of water once every 3 days during the growing stage. Results: Growth parameters, seed yield, and seeds nutritional values were measured. Results revealed that seeds yield from the treated pot using 30% of pyroclastic powder is 4.2 times greater than that of the control. Globally, pyroclastic powder improved the nutritional values of common bean seeds compared to the Control. Fertilizing the soils at the sowing stage significantly (p<0.05) improves the values of the studied growth parameters. The protein content of seeds from treatment at the sowing stage was 1.05 and 1.11 times greater than that from treatment at germination and flowering stages. Conclusion: The application of 30% of pyroclastic powder at the sowing stage is recommended for the cultivation of the common bean in the Adamawa (Cameroon).