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The Effect of Black Light on Plant Growth

blue neon light image by ELEN from

Gardeners should be careful before deciding to use black lights on their plants. Although artificial light can be used for growing a variety of plants, there can be a variety of consequences. While sunlight is full of energy, heat and minerals, artificial light is not. Plants grown through the use of black lights alone will suffer from a variety of consequences while being deprived of natural light.

Black Lights

Black lights, or UV lights, are lamps that emit electromagnetic radiation in the near ultraviolet range of the light spectrum. This specific color exhibited by black lights enhances the vibrancy of fluorescence. Using black lights for art, science and entertainment has grown in popularity. Gardeners can test these lightsin hopes of increasing the vitality and life of plants.

Plant Development

Plants use sunlight by converting solar energy into food through a process known as photosynthesis. Photosynthesis provides the plant with energy to continue biological processes. Fruit production, reproduction, enzyme creation and carbon-building processes all rely on food to properly take place within a plant. Reducing the light given to the plant starves it, inhibiting all of this from taking place.


There are many benefits of growing plants through the use of artificial light. Gardeners and cultivators are able to better control the development of the plant, set timetables and limits on the amount of light and protect their plants from outdoor threats such as pests and disease. Unfortunately, black lights won't be able to offer most plants the amount of light required for functioning growth.

Light Deficiency

A plant grown with only artificial light given off from a black light will experience similar symptoms to those kept in a winter climate. Some plants, like bamboo, which need much less light than common flowers, can be grown. Others, though, will be unable to produce food through photosynthesis. Without food, the plant will stop growing and unable to continue other physiological processes, like replacing damaged cells. Plants that don't wither and die from light deficiency will experience stunted development, discoloration and be unable to reproduce.

Other Consequences

Plants that become weakened through light-deprivation are unable to combat contagions that enter their environment. Infestations of pests or fungi can bring in diseases highly susceptible to plants, This is made worse by the lack of energy available to a plant under UV lights. Many contagions will become lethal to a plant living under these conditions.

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