Plants can help clean up toxic heavy metals from the environment through a process called phytoremediation. This method is cost-effective, eco-friendly, and efficient in removing harmful substances like cadmium, mercury, and arsenic from contaminated sites. Common plants like barley and mustard, as well as medicinal plants like gotu kola and St. John's wort, have been found to be effective in absorbing these heavy metals. By growing these plants in polluted areas and then removing them, the heavy metals can be permanently eliminated, restoring the health of the environment. Factors like plant selection and environmental conditions play a role in the success of phytoremediation.