(This is all in rainbow order.)

Red, quite hard to see,
But it’s just there as autumn leaves to be.

Orange, not the colour of a bee,
But the trickling sap on a tree.

Yellow, which is so bright,
Blasting out of the sun’s rays of light.

Green, it shows on the ground,
Or on the leaves of a springtime tree all around.

Blue, passing on the tides,
Under the sky as a seagull glides.

But in the sky at night,
Is the colour of indigo which is not so bright.

At violet though, I do not tend,
To really say it’s the end.