All plants are symbolically important in the novel, as the well-being of nature matches the well-being of the characters. Taylor is surprised to find an abundance of plants in the desert, just as she is surprised at the quality of her new life in Tucson. Taylor also sees flowers, like the night-blooming cereus flower, as good omens for her future. When she first starts talking, the only words Turtle speaks refer to vegetables, calling to mind the gardens in Tucson that are able to bridge the gap between man-made buildings and the wild bramble of nature.
Yet wisteria vines play a special symbolic role in their relation to Turtle’s character development. Wisteria vines (or “bean trees,” as Turtle calls them) are ugly looking plants at first, just as Turtle started the novel in a comatose, abused state. Yet the wisteria vines are also able to grow in poor soil where no other plants thrive. Turtle too comes back from her unfortunate infancy to become a vibrant little girl. At the end of the novel, Taylor learns that wisteria vines grow thanks to insects called rhizobia that create fertilizer for the plant. This mirrors the way that Turtle needed the support system of Taylor and their makeshift family in Tucson in order to grow.
Wisteria Vines (Bean Trees) and Plants Quotes in The Bean Trees
The wisteria vines on their own would just barely get by, is how I explained it to Turtle, but put them together with rhizobia and they make miracles.