The poem compares the dark sky to the eyes of a young child seeing the world for the first time. At the start, everything feels full of wonder: the child laughs and smiles while looking up at the night. The speaker clearly treasures this innocence and sees real beauty in it.
Then the poem turns. As the child grows, the same beautiful night "becomes something strange," and the glow it once held fades with the years. The final lines are a little tangled, but they seem to suggest that this lost light also stops caring for the "beautiful plants," as if the growing-up world becomes less nurturing and less alive.
The mood moves from bright and tender to quietly sad. The speaker doesn't shout about loss; they simply watch wonder slip away. The poem's feeling is a gentle nostalgia, a sense that growing up can dim the way we see things, even something as simple as the night sky.