What Happens to Plants if They Have No Sun?

Plants need light in order to survive. Natural sunlight allows plants to grow leaves, flower, produce chlorophyll, and more. However, some plants may still grow and thrive even without access to direct sunlight, while some other plants have the ability to flourish with a combination of natural and artificial light. Regardless of what type of lighting source is being used, always remember to water your plants and protect them against pests and diseases.

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The sun will always be the best source of light for plants.

Let There Be Light

Sunlight allows plants to perform photosynthesis, a process which is required for plant growth and health. Photosynthesis allows plants to synthesize glucose from carbon dioxide and water and release oxygen. The blue and red portions of the sun's wavelengths supply plants with their color. The sun naturally provides the plant with the right balance of blue and red rays it needs to survive. Plants that are denied sufficient light will eventually lose their color and die. Plants deprived of light will grow upward, stretching their stems more rapidly that usual, searching for light. This process is known as etiolation and is a survival mechanism that maximizes the plant's chances of getting to light.

Artificial Supplement

Certain plants have the ability to grow and flourish without using the power of the sun. These types of plants are known as low-light plants and medium-light plants. Both of these plant types can survive using artificial lighting sources only. Low-light plants can survive with 50 to 250 foot-candles of artificial light. Medium-light plants can survive with 250 to 1,000 foot-candles of artificial light, but prefer 750 foot-candles or more unless they are receiving doses of natural sunlight as well. If possible, use fluorescent tubes rather than incandescent light bulbs when lighting a plant with artificial light.

Sun Required

While low-light and medium-light plants have the ability to grow with certain levels of artificial light, high-light plants are less likely to flourish with artificial lighting alone. Those who attempt to use artificial lighting for high-light plants should use high-intensity lamps that produce at least 1,000 foot candles of light. Like low-light and medium-light plants, high-light plants do best with fluorescent tubes as compared to incandescent light bulbs. High-light plants require at least three fluorescent tubes in order to thrive. However, high-light plants with no access to direct sunlight are more likely to die.

Warning

While plants need light in order to survive, it is possible for plants to be exposed to too much sunlight and be sunburned. The foliage of the plant will begin to fade, bronze, or crisp. Plants that require shade as well as sunlight include the pansy, the viola, and the nemesia. Other plants are more tolerant of extreme heat and long patches of sunlight. These plants include the black-eyed Susan, the purple coneflower, and the heliopsis. Before exposing your plant to any level of sunlight, or artificial light, make sure you know what type of plant you have and what amount of direct light they prefer.