Cosmos Scientific name Bidens bipinnata L. classified in the Asteraceae. The Cosmos is a species native to North America. The plant is about one year old has upright stems with a height of approximately 25-85 cm central stem the branches. The stems are square and slightly hairy. The stem is purple and not hairy. Twig is a four-sided by a tree outdoors. Propagation is by seed In Thailand can be found in the desolate countryside in general.