In Hughes's poem "As I Grew Older," the speaker has a dream that is overcast with a shadow. The dream was there in the bright sun at one time, but a "wall rose" and the dream became overshadowed. Fortunately, the speaker finds a way to break through the wall so the light can once again shine on his dream. There is a sign of hope as the wall comes down. His "dark hands" find a way to "break this shadow into a thousand lights of sun, into a thousand whirling dreams of sun!"
In Hughes's poem "Dream Deferred," the dream has dried up "like a raisin in the sun." There is no hope for the dream deferred. The dream is gone, dried up or crusted over. The speaker cannot use his hands to make the dream come true, as he did in "As I Grew Older." In "Dream Deferred," the speaker wonders what happened to the dream. Where did the dream go is a good question. In "As I Grew Older," the dream is just hiding behind a wall, a shadow. In "Dream Deferred," the dream is not hiding. The dream has dried up and is no more. The dream is gone:
What happens to a dream deferred? Does it dry up like a raisin in the sun? ...or does it explode?