Describe how photoperiodism affects the flowing times of each type of plant. - Short-day plants
- Day Neutral plants
- Long-day Plants

Photoperiodism is the physiological reaction of organisms to the length of night or a dark period. It occurs in plants and animals. Photoperiodism can also be defined as the developmental responses of plants to the relative lengths of light and dark periods. They are classified under three groups according to the photoperiods: short-day plants, long-day plants, and day-neutral plants.