Nasturtiums are versatile, and here in the African bush, versatility rules. Not only an effective companion plant, nasturtiums are a flavorful and nutritious edible. Both the flowers and the leaves contain the same oils as those found in horseradish, wasabi, and mustard seeds, all of which are known for their antiviral, antibacterial, and antibiotic properties. In our little part of the Zambezi Valley, a few miles upriver from Victoria Falls in Zambia, nasturtiums grow wild.