Thanks - I was aware that the sentence was selected because it was syntactically valid but semantic nonsense, but not so familiar with the background debate. For what it's worth, I do think the poem was successful at extracting meaning from each word, albeit metaphorical. It clearly refers to hibernating seeds: "Colorless" refers to the embryonic nature of the seeds - seeds are indeed white or transparent. "Green ideas" are obviously biochemical ambitions for the future - the seeds do not want to be colorless forever. "Sleep furiously" - they may be hibernating, but they are alive and raring to go!

I was so tickled because even without the background, I thought it was good enough poetry to stand on its own. For what it's worth, I believe conveying mood counts as meaning anyway, but in this case I think the poem is surprisingly coherent and specific.