Cosmos Atrosanguineus is also known as the Cosmos Chocolate. The special dark brown colored flowers indeed smell like chocolate. Cosmos Chocolate is a beautiful border plant that is easy to propagate from root cuttings. Since it is a tropical plant native to Mexico, this plant is not hardy. That is why it is best to dig up the rhizomes of the plant and overwinter frost-free in peat dust and plant them out after ice saints.