The four main characters of this excellent play are Mama, Walter, Ruth and Beneatha. Each of them have a different dream for their lives, and in some cases it is clear that they have more than one dream. However, initially their dreams seem to compete against each other, as for one of them to achieve their dream would mean the death of another character's dream.
The dream of Beneatha is to study to become a doctor, whereas the dream of Walter is to set up his own liquor business with a friend so that he does not have to work serving whites and demeaning himself (as he sees it). For Ruth, her dream is to have a house which can be a home where she can bring up her family and her new baby. Lastly, for Mama, as the matriarch of the Younger family, her dream is above all to be able to create a home that would be nurturing for her family rather than restrictive and unhealthy. Note the way that this is symbolised by her attentive care of her potted plant. This is made clear from her very first entrance into the play:
She crosses through the room, goes to the window, opens it, and brings in a feeble little plant growing doggedly in a small pot on the windowsill. She feel sthe dirt and puts it back out.
The plant can be seen as a symbol of the Younger family that is determined to grow "doggedly," in spite of the unsalubrious conditions it is forced to grow in. In the same way, Mama's care of this plant shows her dream of being able to find an environment where her family can truly flourish.