The poem turns on a small paradox. The title, "Abuzz," and the first line, "busy morning," suggest daytime noise: insects, activity, a world already up and humming. But the last two lines place all of this "at home in the almost / midnight ear." The sound is happening somewhere dark and quiet, inside the listener's own hearing.
One way to read it is that the speaker is lying awake, or just waking, in the small hours, and the ear is full of a faint buzzing that feels like morning activity. It could be tinnitus, or the hum of the night itself. The poem doesn't say, and that openness is part of its charm.
The speaker seems more curious than bothered. Words like "busy" and "at home" make the noise feel almost companionable, as if the ear were a house with lively guests. The mood is hushed and intimate, with a little humor in the mismatch between morning and midnight. The line break after "almost" also makes us hover between night and day.