Disclosed herein are methods for improving fruit production or fruit quality in fruit trees, such as decreasing cold damage, increasing fruit size, increasing fruit quality, and/or increasing fruit set. In some embodiments, the disclosed methods include methods of decreasing cold damage to a fruit tree including applying an effective amount of a composition including DL-β-aminobutyric acid to the fruit tree, thereby decreasing cold damage, for example as compared to a control. In other embodiments, the disclosed methods include methods of increasing fruit size or fruit quality of fruit from a fruit tree, including applying an effective amount of a composition including prohexadione-calcium to the fruit tree after anthesis, thereby increasing fruit size or fruit quality, for example as compared to a control. In further embodiments, the disclosed methods include methods of increasing fruit size of fruit from a fruit tree or increasing fruit set of a fruit tree including applying an effective amount of a composition including 4-chlorophenoxyacetic acid to the fruit tree, thereby increasing fruit size or fruit set, for example as compared to a control.
