Symbol Analysis
Like the inside of our college dorm fridge, green things are growing all over the place in this poem. They're doing it in a good way here, though. Our dorm fridge was a whole lot grosser—trust us.
In lines 6-8, moss and "verdure" cover the area below the bridge, and then earth is described (pretty literally) as green. In line 26, more moss grows, and in 36 we finally see why: it's spring. The poem describes an April night (according to line 46) and the speaker makes no bones about the opportunities green things afford young people and poets.
We should bask in the greenery, he says, and learn to really appreciate nature.
The wild and untamed grove is full of "grass and king-cups" in line 54, and it is here that the young maiden happily connects with the immortality of nature.
Enjoying nature leads to joy, he argues, and the color green symbolizes this joy.