The central theme of “Song of a Second April” is the tendency of life to move on and persist even during change and periods of destruction. The poem portrays the coming of April and spring and how the natural world—as well as human beings—responds to that change. Despite the lingering “mud” and “dingy snow” (Line 4) from a cold winter that should have been destructive to plant life, the perennial hepaticas, the speaker observes, “[a]re here again” (Line 6). Undeterred, the natural world returns to its typical routine. No longer frozen, the streams “run still and deep” (Line 13), and the brooks flow “noisy and swift” (Line 14). Even animals are seemingly unaffected by the winter. The speaker notices butterflies (Line 6), woodpeckers tapping at trees in an orchard (Line 10), and sheep grazing from mullein stalks “in the sun” (Line 16).

Like the weather, bodies of water, and plant and animal life, human beings also shrug off the effects of winter and resume their regular lives. The speaker hears the “rings” of “hammering all day” (Line 7) long, as men, “merry at their chores” (Line 11), repair their homes. The speaker references the shingles that “lie about the doors” (Line 8), suggesting the men are working to fix their snow-damaged roofs.