The poem sets two small scenes side by side and lets the gap between them do the talking. In the first, "you" head out on "morning road in a bottle," a strange, compressed phrase. It could mean a drink carried along, or the idea of the whole morning road being bottled up, something held and tasted. Whatever it means exactly, the person leaves, and does so "alone."
The second stanza turns to the speaker, who spends the whole afternoon "on my knees / in the garden." The image is humble and physical, but it also carries a faint hint of waiting, or even of penance, since kneeling can suggest both.
The title calls them a couple, yet the poem shows them apart, each in their own task. The speaker doesn't complain. The tone is calm, observant, and a little wistful. Nothing dramatic happens, but a quiet distance hangs over an ordinary Sunday, and the reader is left to decide whether it is peaceful or lonely, or both.