French marigold (Tagetes patula).—Robert Bornemann/Photo Researchers
Any of about 50 species of annual herbaceous plants that make up the genus Tagetes in the aster family (Asteraceae), native to southwestern North America. The name also refers to the pot marigold (calendula) and unrelated plants of several families. Marigolds include popular garden ornamentals such as African marigold (T. erecta) and French marigold (T. patula), which have solitary or clustered red, orange, and yellow flowers and usually finely cut leaves. Because the strongly scented leaves discourage insect pests, marigolds are often planted among vegetable crops.