An assessment is presented regarding the use of iron-magnesium production waste for the remediation of cadmium-contaminated soils. The waste contains, mg/kg: Mg 175,000, Fe 52,000, K 30,000, and traces of Cu, Zn, and Co, with no detectable Cd. Garden cress (Lepidium sativum L.) was grown for seven days on a substrate containing 10 mg/l Cd and treated with three doses of an iron-magnesium composite (IMC): 10, 60, and 120 g/m². FeSO₄, MgSO₄, and a combination thereof were used for comparison. Parameters evaluated included germination rate, root length, pH, redox potential, mineralization, moisture content, and metal concentrations in soil and plants (via atomic absorption spectrophotometry); root barrier coefficients (RBC) and translocation factor (TF) were calculated. The high IMC dose (T4, 120 g/m²) maximized Cd immobilization (reducing the mobile fraction by 38 % to 9.6 mg/kg), eliminated Mg deficiency, and stimulated root growth by 30.6 %, but caused soil salinization (TDS up to 740 mg/l) and the accumulation of Ni (up to 39.8 mg/kg) and Co (up to 5.2 mg/kg) in the soil. The low dose (T6, 10 g/m²) reduced Cd availability to 11 mg/kg and increased root growth by 10.4 % without significant salinization (TDS 270 mg/l). Ni and Co were effectively retained by the roots (RBC 1.96 for Ni, >3.0 for Co), and their transport to the shoots was minimal (TF 1.26 for Ni, 0.60 for Co). For short-term application, a dosage of 120 g/m² is justified, provided salinity is monitored. The optimal long-term solution is a dosageof 10 g/m².