What does Celia do with the wreath the speaker gave to her in Song: To Celia?
When Celia receives the wreath from the speaker, she breathes on it and then, instead of keeping it, sends it back to the speaker:
I sent thee late a rosy wreath,
Not so much honoring thee,
As giving hope that there
It could not withered be
But thou thereto didst only breathe
And sent it back to me;
If you interpret Celia's actions here on a literal level, you might think, "Okay, the speaker is very much in love with her. So he sent her a wreath of roses as a gift and as an expression of love. She must not love him back, because she returned the gift. Someone who was glad to receive that gift would have thanked the speaker and then displayed the gift somewhere in the home."
However, as discussed here on eNotes, some readers see a bit more going on in this poem. Notice how the speaker says that he sends the wreath to Celia because "it could not withered be" in her presence, which hints that he believes she holds some kind of divine power over natural things. (He means that, somehow, the flowers in the wreath won't die if Celia is near them.) But then Celia breathes on the wreath ("But thou thereto didst only breathe") before sending it back to the speaker, and after that, the wreath not only smells like Celia but also somehow magically keeps on growing:
Since when it grows and smells, I swear,
Not of itself, but thee.
So, as you consider what Celia did with the wreath, instead of thinking that she just didn't want the gift, you might think that she imbued it with some kind of divine magic, then returned it to the speaker as a gift of her own.