After feeling philosophical upon seeing my first nasturtium seedling come up, I consulted my trusty Norton Anthology of English Literature for the poetry quote I was thinking of. I couldn't find it. A google search did find it, and it is William Blake, not William Wordsworth. (Sorry - I did them in the same semester at Uni and it was a long time ago). It is from Auguries of Innocence:
To see a world in a grain of sand,
And a heaven in a wild flower,
Hold infinity in the palm of your hand,
And eternity in an hour.