Britannica
Sources used in this answer
Why are the red parts of a poinsettia not true petals?
Created from Britannica articles
using AI.
AI can make mistakes, so verify using Britannica articles.
Malpighiales
Weeping willow (Salix babylonica).
The red parts of a poinsettia are not true petals because they are actually modified, colored, leaflike structures known as bracts.
In botany, a bract is a structure positioned beneath a flower or inflorescence. In the case of the poinsettia, these showy bracts serve to surround and frame a central cluster of tiny, inconspicuous yellow flowers.12