Hopkins uses apostrophe, a story, and imagery to convey the message of death, decay, and the fall of man.

Apostrophe occurs when a poet's speaker addresses an absent person or an object. In this case, he speaks to a young girl named Margaret. The speaker comes across her as she is crying over the leaves falling off a tree (called "Goldengrove"). As he addresses her, he pieces together her story, at least as he understands it, and using apostrophe, explains it to us (we eavesdrop on his talk with Margaret).

She is not just crying over the death of the leaves that have fallen to the ground, but is reflecting on the human condition. All things—including, most notably, humans—must die. This is because, according to Hopkins' Catholic (and Christian) theology, Adam and Eve sinned in the Garden of Eden by disobeying God. Now all humans will perish—that is what the "fall" refers to, though Hopkins is also punning on "fall" in the poem's title as both the fall of mankind and fall the season. Ultimately, whether she realizes it or not, by grieving over the death of the leaves, Margaret is grieving over her own eventual death.

Hopkins uses the imagery of decay to underscore his point: for example,

worlds of wanwood leafmeal lie

Wanwood conjures to find sad, fading, sickly wood that has died and leafmeal means dead leaves. Words like "blight" and "ghost" also convey images of decay and death.