Not the colour but -

I know a lady named Mrs Green,
Airy, airy I do,
I know a woman named Mrs Green,
Down by the greenwood side O

She had two babies long and small,
She didn't like them, not at all.

She stuck a penknife in their hearts
She stuck a penknife in their hearts

The policemen came the very next day
And took poor Mrs Green away.

They took her in the Black Maria
And tied her up with old barbed wire.

They hanged her from the cherry tree,
And that was the end of Mrs Green.

The moral of this story is,
Don't stick knives in baby's heads.

Then of course there's always the one that begins:
"Green is the colour of my true-love's teeth."

Sorry if this has been less than helpful - couldn't resist.,
Jim Carroll