The title is the Latin name for the winter wren, a tiny brown bird that stays active through the cold months. The speaker compares their own mood to that bird: "merry like / a winter wren." It's a modest, stubborn kind of cheerfulness, the kind that carries on when the season offers little to be cheerful about.
Then comes a small act of making. The speaker has crafted paper holly, an imitation of the plant we associate with winter festivities. The last lines hold a quiet hope: that this fake holly "might flower as truly / into a gift." The speaker seems to wonder whether something handmade and artificial can become as real and generous as a living thing blooming.
The mood is gentle, humble, and a little wistful. There's warmth in the effort, but also some uncertainty. The poem suggests that a handmade offering, like the poem itself, may not be natural, yet it can still be true.