Mrs. Dubose verbally harasses the children each time they walk by her house. She is especially insulting about Atticus. So much so, that Jem tries to get even by chopping down her garden. Ironically, Atticus makes Jem and Scout read to Mrs. Dubose as a punishment for trying to destroy her garden. At the time, the children did not realize that Mrs. Dubose was a morphine addict trying to get clean. By reading to her, Jem helped her kick her morphine habit before she died.
Jem and Scout loathe walking down Mrs. Dubose's street because she is often on the porch, hurling insults their way.
An elderly lady confined to a wheelchair, Mrs. Dubose is a peevish neighbor, who spends her time fault-finding. Whenever Jem and Scout pass by her house in nice weather, she is on her porch, ready to hurl insults and negative prognostications upon the children.
In Chapter 11, Scout narrates that it is impossible to walk to town and avoid the house of Mrs. Dubose except by going a mile out of the way. Sometimes she is inside, but if she is in her wheelchair on the porch, encounters with her are inevitable, even if they walk on the opposite side of the street, because she will shout her insults across to them. Scout narrates,
...when we passed, we would be raked by her wrathful gaze, subjected to ruthless interrogation regarding our behavior, and given a melancholy prediction on what we would amount to when we grew up....
Mrs. Dubose's is a choleric nature; for instance, when she once heard Jem refer to his father as Atticus, she flew into a torrent of anger, calling Jem and his sister "disrespectful mutts." Then, one day as Jem and Scout go to town so that Jem can purchase a steam engine, she makes a personal attack upon the boy, contending that he has broken Miss Maudie's scuppernong (a wild white grape) arbor; she also insults Scout, saying that she will not amount to anything if she does not stop wearing overalls. Instead, she will just be a waitress in the local "greasy-spoon" eatery, the O.K. Cafe.
Although Jem has patiently suffered Mrs. Dubose's attacks upon Atticus for his "lawing for n****s" and her comparison of Atticus to the "trash" he defends, this one upon his personal integrity Jem cannot bear, along with the further "philippic on [their] family's moral degeneration." On their return from town, in the absence of Mrs. Dubose on her porch, Jem grabs the baton he has purchased for Scout and runs into her front yard. There he cuts the tops off every camellia bush that Mrs. Dubose owns. After completing his act of revenge, Jem bends the baton over his knee and snaps it into two, tossing it to the ground. Scout describes his actions as "having gone mad."