Can Colored Lights Affect How Plants Grow?
Plants react differently to different colors of light.
Everyone knows plants are food factories, and most are aware that their energy source is light. This transformation of light into food is called photosynthesis. What may be news to you, however, is that the color of the light has a measurable impact on the amount of energy a plant absorbs. The reason for this is the colors in light have different wavelengths and those wavelengths, depending on whether they are short or long, provide different levels of energy.
The highest energy light is at the purple or violet end of the color light spectrum. Purple and violet lights have short wavelengths and thus lots of energy. At the other end of the spectrum, you will find red light which has long wavelengths and emits lower energy.
Regardless of whether the color of the light is red or purple the plant will absorb some amount of energy from the light it is receiving. Green light is the least effective for plants because they are themselves green due to the pigment Chlorophyll.
Different color light helps plants achieve different goals as well. Blue light, for example, helps encourage vegetative leaf growth. Red light, when combined with blue, allows plants to flower. Cool fluorescent light is great for cultivating plant growth indoors.
Knowing that different colors of light can affect what a plant does is important in a world that depends on plants for food. Advanced LED technology is now making it possible to control the kinds of colored light we provide plants in controlled environments.
We can now design lighting to encourage flowering or to produce higher fruit yields for example. Many plant functions can be enhanced and promoted just by knowing what light colors they react and respond to.
For a hungry world just waking up to the effects of Global Warming, this is critical. It will allow us to provide environmentally friendly alternatives to help improve crop quality and growth without having to resort to powerful fertilizers and genetically modified food.