What a very interesting question. Colors are created by the light spectrum. The different shades we see are due to different levels of light and radiation coming from them.
This means that the different colored lights of the spectrum would definitely have different effects on the plants that they cause photosynthesis within. Here is a quick run-down of how different color lights make plants grow.
- Green Light: Since most plants are green already due to their high volume of chlorophyll, green light has very little benefits to plants aside from allowing for photosynthesis. However, plants that grow under green lights do tend to end up with VERY green leaves and stems. This aesthetic benefit is one of the few you will see from green light exposure for hydroponics systems. If you want to experiment with different light colors in your hydroponics system, leave green light out of the equation as you will see very few benefits from it.
- Blue Light: Plants love blue light. The blue light stimulates the growth of the leaves of your plant. It penetrates the extremities of the plants and makes the leaves and blooms rapidly grow and expand. The easiest way to get the benefits from blue lights in your hydroponics system is to use fluorescent lights that cast a blueish hue.
- Red Light: Red light can be a double edged sword in gardening. The heat that comes from red light is more intense than the other colors in the light spectrum, and blooms love heat. Your flowers will blossom quickly and largely under the glow of red light. However, if exposed to too much red light, the plants will become overwhelmed and will begin to shrivel. If you choose to use the benefits of red light, make sure to only use it sparingly. Alternating red and blue light can be very beneficial to most plants
- Orange Light: Orange light has the same affect on plants as red light, only to a lesser extreme. If you can’t be around to monitor the exposure of red light, orange light might be a good alternative as it can be left on the plants for longer periods of time without causing the over-exposure.
- Yellow or White Light: This is the form of light the plants usually receive from the sun or typical grow light bulbs. Yellow and white light promote photosynthesis, which is necessary for proper plant production, but other than that, their beneficial effects on plants are nothing special.
- Violet Light: Some people call these lights black lights. If you want your garden to bloom and thrive, steer clear of the velvet lights. They will do very little for your plants. The only reason we would ever recommend using these lights in a gardening atmosphere would be if you were doing some kind of experiment with colored lights and plants and wanted to prove the benefits that come from the other colors and light sources we have listed here. For your personal hydroponics garden, violet light can be left out of all equations.
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