Cosmos plant is heat-loving annual plant. The flowerheads may be a bowl or open cup-shaped and sit atop long stems. Pinch off spent flowers to encourage continuous bloom. Pinching stem tips can reduce height and encourage branching. Cosmos plants are either herbaceous perennials or annuals that can reach heights of 0.3 to 2 meters (1 to 6 feet 7 inches). Their leaves are simple, sometimes pinnate or bipinnate, and grow in pairs opposite each other along the stems. The flowers form in clusters known as capitulums, featuring a circle of wide ray florets surrounding a center of disc florets.

The color of the flowers varies significantly among different species within the genus. Cosmos includes several types of ornamental plants that are popular choices for gardens. Over time, many hybrids and cultivated varieties have been developed and given specific names.