Over in our Symbols section, we break down the symbolic significance of the novel's "bean trees" more fully, so feel free to skip on over there for a more detailed discussion of their meaning. For those of you who don't want to beat around the bush, we'll give you the short answer here.
Children are great at noticing when two things look alike. In The Bean Trees, three-year-old Turtle gets to thinking that the seed pods on wisteria vines look an awful lot like the pods that hold beans. So, she figures that the wisteria vines must be bean trees. The logic may not be totally sound, but give her a break—she's three!
The novel takes its title from Turtle's mistake for the simple reason that wisteria vines are the novel's most important symbol. Why's that? Because, as Taylor and Turtle eventually learn, they have the ability to thrive in very poor soil, all thanks to their symbiotic relationship with microorganisms called rhizobia. The rhizobia live on the roots of the plant, and their everyday activities convert nitrogen from the soil into fertilizer for the roots.
The symbiotic relationship between wisteria and rhizobia results in a win-win for everybody, including Barbara Kingsolver. For her, the tiny ecosystem makes a perfect symbol of the effect that loving partnerships and communities can have in the lives of human beings. Even though life itself can sometimes be "poor soil," The Bean Trees suggests that symbiotic relationships—relationships of reciprocal care—can let anyone thrive in even the roughest circumstances.