Annelle Dupuy (Daryl Hannah), a shy, awkward beauty school graduate, moves to a northwestern Louisiana town where Truvy Jones (Dolly Parton) hires her to work in her home-based beauty salon.
Meanwhile, M’Lynn Eatenton (Sally Field) and her daughter, Shelby (Julia Roberts), busily prepare for Shelby’s wedding that is being held later that day. They, and Clairee Belcher (Olympia Dukakis), the former mayor’s cheerful widow, arrive at Truvy’s to have their hair done. While there, Shelby, who has type 1 diabetes, suffers a hypoglycemic attack, but recovers quickly with the women’s help. M’Lynn reveals that due to Shelby’s medical condition, her doctor advises against her having children. Shelby had considered ending her engagement to her fiancé, Jackson (Dylan McDermott), so he would not be deprived of children.
Grouchy and sarcastic Louisa “Ouiser” Boudreaux (Shirley MacLaine) arrives at the salon and immediately begins interrogating Annelle about her background. Annelle tearfully reveals that her no-good husband, Bunkie, is evading the police and has taken all their money and the car. Annelle further admits she is unsure her marriage is legal. Shelby, sympathetic, invites Annelle to the wedding reception where she meets bartender Sammy DeSoto. Soon after, Annelle, following a short-lived wild streak, becomes deeply religious, annoying everyone, including Sammy.
During the Christmas holidays, Shelby announces she is pregnant. Everyone is thrilled except for M’Lynn, knowing it is too risky. Truvy encourages M’Lynn to instead focus on the joy a new baby brings.
Shelby has a baby boy, Jackson Jr., but soon develops kidney failure requiring regular dialysis. Around Jackson Jr.’s first birthday, Shelby undergoes a successful transplant with M’Lynn’s donated kidney. Shelby recovers but four months later, Jackson arrives home to find her unconscious. Shelby is comatose, having contracted an infection in her central nervous system due to the suppressive therapy that keeps her body from rejecting the kidney. After doctors determine Shelby’s condition is irreversible, the family jointly decide to remove her life support.
After the funeral, M’Lynn breaks down but the other women comfort her. M’Lynn gradually accepts her daughter’s decision to have risked her life in return for a few special years of motherhood. Annelle, now married to Sammy and pregnant, tells M’Lynn she wants to name her own baby after Shelby, as she was the reason she and Sammy met. M’Lynn approves, stating, “Life goes on.”
At the town Easter Egg Hunt, Annelle goes into labor and is rushed to the hospital.