Tithonia diversifolia is a species of flowering plant in the family Asteraceae that is commonly known as the tree marigold, Mexican tournesol, Mexican sunflower, Japanese sunflower or Nitobe chrysanthemum. It is native to Mexico and Central America but has a nearly pantropical distribution as an introduced species. Depending on the area they may be either annual or perennial. It has shown great potential in raising the soil fertility in soils depleted in nutrients.

Research has shown its potential in benefiting poor African farmers. This plant is a weed that grows quickly and has become an option as an affordable alternative to expensive synthetic fertilizers. It has shown to increase plant yields and the availability of soil nutrients such as nitrogen (N), phosphorus (P), and potassium (K).