This study aims to examine the effectiveness of lamtoro seed POC as a substitute for commercial nutrition in the growth and yield of mustard plants in the axis hydroponic system, and to obtain the right nutritional formulation in the lamtoro seed POC by setting the EC value (Electrical Conductivity). The study was conducted at the Green House of the Faculty of Agriculture, University of Muhammadiyah Yogyakarta in September - November 2018. The study used a single factor field experiment method, which was arranged in a completely randomized design (CRD), namely the first nutrient factor AB Mix and nutrition POC lamtoro seeds concentrations of 0.5 mS/cm, POC seeds of concentrated lamtoro were 1.0 mS/cm, POC seeds were 1.5 mS/cm thick, and 2.0 mS/cm. Tests on each treatment were repeated three times. The results showed that the nutrient administration of lamtoro seed POC can be used as a substitute for commercial nutrition with concentrations of EC values of 1.0 mS/cm.