Long-day plants are those that require longer daylight hours to flower and grow. Typically, they thrive when exposed to at least 14 to 16 hours of light each day. These plants often bloom in late spring or early summer when the days are longer, taking advantage of the increased sunlight to produce flowers and seeds. Examples of long-day plants include spinach, lettuce, and clover. Gardeners often use artificial lighting to extend the day length for these plants, especially in regions where natural daylight is limited. This technique helps maximize growth and yield during the growing season.