In addition to sunflowers, there are a few common plants that can help remediate soil toxicity. Given the degree to which your land has so sadly been abused, you might want to try planting a few different species. Alpine pennycress, Indian mustard, black mustard, and morning glory all absorb toxins in the soil. As for varieties of sunflowers, research is being done to determine if certain cultivars are more effective than others. You would do well to plant Helianthus annus ‘Mammoth’, which is a true sunflower. All the best with your admirable endeavors! We certainly hope you end up with a cleaner environment.
In addition to sunflowers, there are a few common plants that can help remediate soil toxicity. Given the degree to which your land has so sadly been abused, you might want to try planting a few different species. Alpine pennycress, Indian mustard, black mustard, and morning glory all absorb toxins in the soil. As for varieties of sunflowers, research is being done to determine if certain cultivars are more effective than others. You would do well to plant Helianthus annus ‘Mammoth’, which is a true sunflower. All the best with your admirable endeavors! We certainly hope you end up with a cleaner environment.