Once you start growing vegetables and other plants, you may want to know how to make them grow better. A common question is: does the color of led grow light bars affect the growth of plants?

There is no doubt that the color of led grow light bars will affect the growth of plants, but the effect is more obvious in low light intensity. Red light and blue light were the most effective on plant growth, while yellow light and green light had the least effect. Ultraviolet rays can damage plants and cause leaves to burn. Growers often use led grow light bars to optimize plant growth.

What is the effect of the color of led grow light bars on the growth of plants?

Blue light should be used when the plant is only a seed and is just germinating. Blue light is very important at the beginning of plant growth because it increases the amount of chlorophyll formed. Some seeds will not germinate without blue light.

Red and blue light are important when the plant matures and begins to bloom. This helps them produce more leaves and more crops. Purple light can be used at any time of plant life to enhance the color and taste of the plant.

What is the visible light and its relationship with plant growth?

The light we can see – visible light – is just a small part of the whole electromagnetic spectrum. Electromagnetic energy – light – can take many forms. Including: visible light, gamma ray, infrared, radio wave, microwave, X-ray, etc.

Although some forms and colors of light are beneficial and even necessary for plant growth, other forms of light may harm plants. The following figure shows that visible light is only a small part of the whole electromagnetic spectrum:

So why do plants need light?

Plants use light to make their own food through photosynthesis. Chlorophyll, the green pigment in the leaves and stems of plants, uses the energy of visible light to convert carbon dioxide into food. Therefore, the wavelength of visible light is used for plant growth. But can we adjust or increase the amount of light we provide so that our plants can grow faster or healthier? The short answer is yes.

In visible spectrum, red and blue are the most important colors to achieve the best plant health and maximize plant growth. Ultraviolet light is actually harmful to plants, while green and yellow light have little effect on plants. Details of each light color and its effects on plant health and growth are listed below.

Ultraviolet Light

Ultraviolet, also known as ultraviolet, is usually considered harmful to human body. If a person is exposed to too much ultraviolet light, they will get sunburn and may have other negative effects.

Just as long-term exposure to ultraviolet is harmful to human body, high-intensity or long-term exposure to ultraviolet is harmful to plant growth. The less ultraviolet radiation, the better the plant grows.

Violet Light

Violet light is good for plants. Violet light has higher energy, so when plants are exposed to purple light, the color of plants, the taste of fruits and vegetables will be enhanced, the aroma of plants will be better, and the amount of antioxidants produced by plants will be increased. So in general, violet light helps plants grow and can be used to protect them from harm.

Green Light

Plants absorb many kinds of light, but reflect green light. That’s why plants usually have green leaves. Most green light is used to increase chlorophyll production and make plants greener.

Although green light is not as essential to plant growth and health as red or purple light, green light can make plants look greener, so it is very useful in commercial greenhouses where customers view and choose plants to buy.

Red Light

Red light carries less energy than other colors and is not very effective in itself.
But when combined with blue light, the red wavelength is very helpful for mature plants. Red light helps flowers bloom. When combined with red and blue light, the number of leaves a plant grows greatly increases.

Adding 10-20% blue light makes the plant grow healthily and compact. And far red light, whose wavelength is lower than ordinary red light – similar to near-infrared wavelength. Far red light helps plants produce more. Far red light does this by accelerating the process that plants experience at night.
Night is the time for the flowers to mature. By accelerating the night process, red light helps to produce more production for your plants.

Choose the Right Led Grow Light Bars

While it may be tempting to choose light that focuses on color, plants need a little bit of each color. Providing your plants with every type of light will benefit them the most.

If you have a higher concentration of blue and red light than yellow and green light, then the function of the plant will be enhanced. Other considerations when choosing light are the intensity of the light and the time the plant is exposed to it.

Higher intensity will increase the photosynthesis of plants. The duration of outdoor light depends on the sun, but in greenhouses, it is recommended to turn on the lights for 12 to 14 hours a day for optimum results.

Recommended Led Grow Light Bars

For more comprehensive and updated articles with specific suggestions, I have organized a separate article. Here is a quick summary of the different types of lights:

  • High intensity discharge grow light are mainly used for major growth operations because they use more electricity and generate more heat.
  • Fluorescent grow light lifespan is longer, will produce a lot of blue light. They may not provide complete chromatograms, but they are effective for leafy plants such as herbs and lettuce. They are chosen because they are durable, energy efficient and do not generate a lot of heat.
  • LED grow light bars are designed to produce red and/or blue light. They are increasingly popular in indoor greenhouses for amateurs, but they do not produce very high intensity, so they are not suitable for large-scale growth operations.
  • Incandescent grow light are not suitable for greenhouses. These are often used for aesthetics rather than function. Although they are cheaper than other types of lights, they do not provide the intensity that plants need.

How Far Should the Led Grow Light Bars Be from the Plant?

The distance from the led grow light bars to the plant depends on the type of led grow light bars used:

  • High intensity discharge : 5 to 8 feet above plants
  • Fluorescent : 4 to 6 inches above plant
  • Led grow light bars: 14 to 30 inches above plant

You can use your lamp boxes, chains and bulbs to make your own led grow light bars. Chains are used to adjust the distance between light and plants. As the plant grows, you need to adjust the distance of led grow light bars above the plant.

Does Light Intensity Affect Plant Growth?

Yes, higher light intensity tends to increase the rate of photosynthesis. This is because higher light intensities accelerate the reactions required for photosynthesis. Greenhouse glass will reduce the light intensity of photosynthesis of plants, so it is recommended to supplement lighting.

Do Plants Grow Under White Light?

White light is full spectrum light. Some plants can usually use because the sun produces full spectrum light. Plants grow best in natural sunlight, and white light can also be used in greenhouses, but you may need to try to see which light is best for your plants.