Botanical Latin has a large number of words for the color yellow. For example, words beginning with "flav," as in flavens and flaveolus, all mean yellowish in color, while "flavus" means pure yellow.
The word "luteus" also means yellow. "Albidus" and "albus" mean white, and "nivalis" describes a plant that is white as snow.
Sometimes the Latin words that apply to plants have been derived from Greek roots. For example, the word for sunflower-helianthus-comes from "helios," the Greek word for sun and "anthos" meaning flower, so the name itself suggests that the flower is yellow.
Another association with the sun is the word "rays," which is the botanical term for the narrow petal-like parts of daisy flowers. Another plant with "helio" in the name is heliopsis, which is a yellow daisy-type flower with petals and stems that are not as stiff as those of the helianthus flowers.
The term "heliotropic" describes how some flowers follow the sun across the sky. The Greek word for turning is "trope," and plants that are described as heliotropic actually do turn their flowering stems and flowers to follow the sun across the sky.
