The speaker stands in front of green leaves on the last morning of August and tells themselves to hold on to the moment. The title, "Valediction," means a farewell, and the poem feels like one: a goodbye to summer, but also a quiet effort to keep hold of what makes life good.
To do this, the speaker lists other memories. There are sailboats rocking at anchor, bright beach huts by the Atlantic, and the strange cries of shearwaters coming back to their cliffs before dawn. Then come smaller, homelier things: the smell of a well-loved pub and sitting across a table from a life partner. These ordinary pleasures sit right beside the dramatic seaside images, as if they matter just as much.
The mood is tender and a little wistful, but not sad. The ending looks ahead to winter, which "promises" a ladder to the moon. The speaker seems to find that even the cold season holds something worth remembering.