The central symbols of the poem "Mother to Son" by Langston Hughes are the ideal "crystal stair" and the contrasting rickety staircase which the mother says she has actually had to ascend and which her son must also learn to climb. The crystal stair is mentioned but not described, and it is an ideal because it does not correspond to anything in real life, since staircases are not made of crystal. The reality, however, is described in some detail: it is a staircase with tacks and splinters sticking out and boards torn up, lacking carpet in places. This is a journey that has sometimes been painful and always uneven, though the speaker has been able to continue climbing upwards, despite the difficulties.

The poem also contains the symbolism of light and darkness. The mother says that she has sometimes had to turn round corners, for the staircase does not lead straight ahead:

And sometimes goin’ in the dark

Where there ain’t been no light.

It is dangerous to climb a staircase in the dark. The light, therefore, stands for safety and certainty, as well as hope. It is one of the main properties of crystal, that it sparkles in light and reflects it. The real staircase, however, is often plunged into darkness, and this darkness covers a multitude of dubious, difficult choices, as well as being dangerous.

The poem's main symbol is the rough staircase the mother climbs every day. It has, according to her:

tacks in it,

And splinters,

And boards torn up,

And places with no carpet on the floor

He had a dream in which he saw a stairway resting on the earth, with its top reaching to heaven, and the angels of God were ascending and descending on it. There above it stood the Lord, and he said: "I am the Lord, the God of your father Abraham and the God of Isaac. I will give you and your descendants the land on which you are lying. Your descendants will be like the dust of the earth, and you will spread out to the west and to the east, to the north and to the south. All peoples on earth will be blessed through you and your offspring."

In this context, the stairway takes on a new resonance that breathes hope, promise, and aspiration into the black people, who, like the oppressed ancient Israelites, are God's beloved children. No matter how dreary and splintered her staircase is, the mother is seeing herself as one of God's angels ascending and descending it and wants her son to be on that staircase so that he too will receive God's blessing.

In "Mother to Son," Hughes uses a number of symbols. First of all, in lines four to six, the "splinters," torn-up boards, and floor without carpet are symbolic of the mother's hard and problematic life.  This is further reinforced in the seventh line with the single word "bare," which emphasizes the difficulties she has encountered. The staircase itself has significance since it acts as a symbol of life's journey. 

Later in the poem, the mother again uses symbolism when she talks about the course of her life. Reaching the landing, turning corners, and navigating in the dark, for example, are all symbols of the specific obstacles she has faced and overcome during the course of her life.

Finally, in the first and last lines of the poem, the word "crystal" has symbolic meaning. Specifically, the word suggests wealth, affluence, and luxury; it is used by the mother as a symbol of the life she hoped to have. 

The poem “Mother to Son”, by Langston Hughes, is an uplifting, hopeful poem about never giving up.  The main symbolism in the poem is when Mother compares her life to a staircase.  She says, “Life for me ain’t been no crystal stair.”  By this, she means that life has not been easy, and her journey through life has been like climbing a staircase.  As a black woman, her journey has been hard, and as she describes it, the staircase she has had to climb has “tacks in it”, “splinters”, “boards tore up”, “places with no carpet”, and is “bare”.  It has not been a smooth and easy journey of life; the kind of life that a crystal staircase would provide.  Instead, the Mother has led a life full of obstacles and hardships in her metaphoric climb up the stairs from birth to death.

She is hopeful for her son, and she encourages him to keep climbing like she has.  She tells him in his own personal journey to not turn back or “set down on the steps.”  Like her, he must keep going and reach for what he wants in life. 

The staircase is symbolic of progressing through life and having the will to keep climbing.   It is also a symbol for the journey we all take in life.