That’s a lovely way to describe it—plants do have their own mood swings. The green you see at dawn is mostly chlorophyll reflecting light, but as the sun moves, the light’s angle and intensity change, so the leaves can pick up different pigments. During the day, you might see a little blue‑ish tinge from anthocyanins, and by sunset the light warms up, making the green look olive. It’s like the tree is tuning its own soundtrack to the day’s rhythm.