The main theme of this short poem by Langston Hughes is the harmful result of suppressing or deferring dreams. Hughes offers several possibilities as to what might happen to a dream when it is "deferred" in this way, but none of them are positive outcomes.

First, he suggests that if a dream is deferred, presumably because the dreamer has been prevented from fulfilling himself as he intended to, it might "dry up" like a raisin and die. Alternatively, it could "fester," becoming something akin to a running sore; or it might begin to rot like meat, or "crust" over. In all of these images, Hughes compares the dream to a foodstuff which is only worth eating for a brief period of time. If the dream is forced to wait, it will soon reach a point where it cannot fulfill its original and intended potential. Instead it will simply become something unworthy of consumption.

Finally, Hughes offers two extreme possibilities for the result of a deferred dream: either the dream will "sag" and pull down on the unfulfilled dreamer like something heavy, or it might "explode."

Hughes is writing in this poem about the experience of Black Americans, many of whose dreams were, particularly in his time of writing, deferred by necessity: they were forced to wait before they could take what they wanted. The final line, italicized, is a warning that dreams cannot be deferred forever, particularly not the dreams of an entire community, without violence or revolution becoming a threat.

The main theme of Langston Hughes’s poem “Harlem” is that forcing another person to delay the achievement of their dreams, or being forced to delay one’s dreams, can have devastating and wide-reaching effects.

The speaker asks a number of questions in response to the initial one: “What happens to a dream deferred?” (line 1). First, he asks if it simply dries up, like a raisin left out in the sun? This would make the raisin fairly unpalatable. Next, he asks if the deferred dream will “fester like a sore” that oozes pus or blood—a pretty uncomfortable and gross idea. Third, he asks if the delayed dream will begin to “stink like rotten meat,” or, fourth, if it will “crust and sugar over” like some too-sweet dessert left to sit out and get old. Neither would be edible or enjoyable. Next, the speaker suggests that the dream will begin to wear on a person, to become a burden “like a heavy load” would. Each of these five comparisons uses a simile to compare the deferred dream to something else, something unpleasant.

Finally, the speaker asks, “Or does it explode?” This line is set apart, on its own, as well as italicized (which provides emphasis), and it is also the only metaphor in the poem, comparing the deferred dream to something that would explode, like a bomb. For these reasons, we might surmise that this is the real answer, the truest answer to the first question. The speaker’s other suggestions as to what happens to a deferred dream are much smaller, affecting only one person or place, but a bomb affects many people and can be terribly destructive to a large area. This leads us to the poem’s main idea: that a deferred dream doesn’t simply die or wither away; it builds in pressure until there is a figurative explosion, perhaps of anger or resentment.

That the poem is called “Harlem” leads to the related idea that the dream of racial equality for Black Americans cannot be deferred without causing destruction and harm. Harlem is a predominantly Black borough of New York City. One could read the poem as a warning that, if Black Americans’ dream of equity and fairness is deferred by white society, the effects will be devastating for all.

The theme of “Harlem” is provided in the opening question, as the speaker asks the reader to consider the effects of putting off fulfilling one’s dream. The theme is the choice between optimism and pessimism.

The reader does not necessarily have to choose any of the options; in fact, the speaker offers mainly offers more questions, not answers, and the one statement provided is qualified with “maybe.” Only one of the options sounds remotely positive, in being “sweet,” but it is an overdone kind of sweetness, “crusty” and “syrupy.”

Overall, the speaker suggests that deferring a dream will not have good consequences. As “explode” is the last option given, it seems likely that is the one the speaker believes will result, but the choice is left to the reader.

The poem “Harlem” by Langston Hughes, is one of many poems he wrote about fulfilling one's dreams. Written primarily for the African American community, this poem addresses the idea of what happens when you don’t go after your dreams and you put them off or “defer” them to later.  Hughes uses symbols and imagery to explain what can happen if you don’t move forward and accomplish your dreams.  He suggests that if you put off your dreams they will “dry up,” “fester like a sore,” begin to “stink like rotten meat,” or “crust over.” More importantly, they may become like a “heavy load,” or they will simply “explode.”  These are all descriptions of the psychological consequences of not following your dreams.  Unfulfilled dreams will eventually cause one to give up or let their dreams go. 

Hughes’ series of dream poems are meant to encourage and convince others that dreams are obtainable and necessary to survive. I’ve included another short poem by Hughes to show the similarity of this recurring theme.

Dreams by Langston Hughes

Hold fast to dreams
For if dreams die
Life is a broken-winged bird
That cannot fly.
Hold fast to dreams
For when dreams go
Life is a barren field
Frozen with snow.