These are myths I made up, not ones I’ve heard before.
When the Earth was formed, everything was given a role and a place to spend eternity. The seas were never to come on land, the trees were to stay rooted in the ground, the sky was to surround the Earth never touching the ground, while the grass was to stay on the ground never being in the sky. Things were fine for millennia, things stayed out as they were told to be in their hazy nondescript color scheme.
But the sky was sad, never touching the ground. Growing sadder by the passing days, the sky turned blue to reflect it’s sad mood.
The Grass was jealous of the sky, being forced to stay on the ground and never able to leave it, it turned green with envy.
After turning the colors they remain to this day, all the trees and flowers and animals chose their own colors, some out of necessity, some out of desire. But none as sad as the jealousy and envy of the grass and the sky.