Plants are the most abundant symbol in Counting by 7s. They are one of Willow's obsessions, and it is through her plants and gardens that the author tells the story of her transformation. According to Willow, “to know [her] is to know [her] garden” (15). After her parents' death, her beloved garden symbolizes the past and because she cannot return to it, she abandons her interest in it. After processing her grief, she is able to start thinking about her garden again, and the sunflowers and courtyard garden project brings her new family together.

Willow sees herself through the different plants she loves when she feels comfortable. When adjusted to her new life with the Nguyens, she compares herself to the new sunflowers, tentatively putting down roots. When a maintenance man throws her rooftop cuttings away, she sees this as a symbol of impermanence, and she mentally prepares to leave the Gardens of Glenwood to face whatever else her future holds.

Willow also compares herself to the lucky acorn Mai finds—she is a survivor and is ready to begin her life again with her new family. This symbol appears again when Willow plants the acorn—and herself— at the end of the novel, sending down permanent roots with plenty of space to grow.