Are Night-Blooming Flowers Dependent on the Sun?

Reasons for Night Blooming

• The full function of a flower is to attract pollinators, which aid in the reproductive cycle of the plant by carrying its pollen to other flowers. The shape of the flower, the color, scent, pollen and nectar are all designed to attract specific pollinating creatures to the plant. Plants that bloom at night are normally pollinated by bats, moths, and rodents who are nocturnal themselves. By closing during the day, the flower guards its pollen from wind and other insects, saving it for night when it opens to its preferred pollinators.

Triggers

• The trigger for a plant to bloom depends on its individual biology and varies greatly between plant species. For night-blooming plants, a decrease in temperature or light, or an increase in humidity are triggers to open the blossom. The plant may sense the same triggers, though inverse, to close at the end of the night, or it may have an internal rhythm that indicates a time to close. In most plants, a combination of these triggers is what finally guides the plant to open or close its blossom.

Role of the Sun

• For many night-blooming flowers, the sun is an important factor in the blooming rhythm and reproductive cycle. The sun provides light and heat and also affects the amount of humidity in the air. In addition, all plants are dependent upon the sun for photosynthesis, the process by which plants produce their energy.

Environmental Irregularities

• Some plants require very specific conditions in order to bloom, while others bloom under a more forgiving range of conditions. To trigger blooming indoors or in landscapes is difficult with some plants, because it is tricky to imitate the natural environment that the plant requires to blossom. Plants can maintain seemingly perfect health but if lacking a specific trigger will fail to blossom.