The invention relates to a strengthening measure for repairing the polluted soil plant, in particular to a method for combined repairing the soil polluted by heavy mental lead. The method is that the Petunia is planted on the soil which contains the polluted lead. When the Petunia becomes mature, mixed chelating agent is added to the soil. The mature Petunia as a whole are removed or grained after the soil balances for 10 to 15 days, thus achieving the purpose that the Petunia repairs the soil polluted by the lead. The added quantity of the mixed chelating agent is 7.5mmol/kg soil. The strengthening measure adds the mixed chelating agent when maturing to strengthen the total amount of the lead which is richly collected by the Petunia above the soil, and to grain the Petunia above the soilto realize the purpose of treating the soil polluted by the lead which is characterized by high efficiency of repairing, strong feasibility, greatly reduce the environmental risk and harm to the human health, etc.