Different colors of light can have different effects on plant growth.
For example, blue light is known to promote vegetative growth and is often used during the vegetative stage of plant growth. On the other hand, red light is known to promote flowering and is often used during the flowering stage. Green light is less effective at promoting plant growth, as it is mostly absorbed by the chlorophyll in the leaves and is not used in photosynthesis.
The best color light for plant growth is a combination of red and blue light, with a small amount of green light. This spectrum is known as “full-spectrum” lighting, as it mimics the natural sunlight which plants evolved to thrive under.
Red light promotes flowering and fruiting, while blue light promotes vegetative growth. Green light, while not as important for photosynthesis, can be beneficial for overall plant health and can help to reduce plant stress.
Some of the optimal ranges of different coloured light are:
It’s worth noting that different plants have different light needs, and plants that require high light intensity such as succulents and cacti, may benefit from more red light, while plants that require low light intensity, such as ferns, may benefit from more blue light.
Green light is considered less effective for promoting plant growth, as it is mostly absorbed by the chlorophyll in the leaves and is not used in photosynthesis. Additionally, plants are not able to see the green light, so it is not necessary to provide green light for the plants’ growth.
Too much of any color light can be detrimental to plant growth. For example, overexposure to red light can cause plants to stretch and become leggy. Overexposure to blue light can cause plants to become stunted and bushy. Overexposure to any light can also cause plants to dry out, so it is important to provide appropriate light intensity and duration.
It’s worth noting that UV light can be harmful to plants as well as to humans. UV light can cause damage to the chlorophyll, which can lead to yellowing and wilting of the leaves. UV light can also cause damage to the DNA of the plant, which can lead to mutations. So, it’s important to ensure that the UV light is filtered out when using artificial light sources for plant growth.