In Kenya, an experiment aims to turn sand into fertile soil

On a remote Kenyan island where the ground is sandy and freshwater is scarce, an innovative experiment is reshaping how food can be grown. Soil microbiologist Su Kahumbu works to transform barren ground into fertile soil using microorganisms, organic waste and moisture-saving techniques. Early results show trees and beans taking root. Similar methods are also helping communities tackle polluted soils in cities.