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cannabis grow light spectrum

Cannabis grow light spectrum

Red & Far Red / Infrared Light (660 nm & 730nm)

One way green light is helpful is it penetrates further down into the canopy than red and blue light, which get mostly absorbed by the upper leaves. This adds to amount of photosynthesis happening to leaves further down on the plant.

LED grow lights use custom color spectrums to get plants to grow more efficiently

If you have to choose between one or the other, it’s generally recommended to use the flowering light spectrum (more red) for the whole grow. This results in bigger yields watt-for-watt. However, you can successfully grow buds in the blue light spectrum for the whole grow, and many growers do this with excellent results. Some growers even claim they like their quality better under blue lights!

One of the most common ways you’ll see light measured is with lumens. Lumens measure “luminous flux” which is a fancy way of saying that it’s how much light you can see as a person. It measures how “bright” something is to human eyes, and it’s weighted so that light we see counts more than the light we don’t see as well. The amount of light received at a particular point in space is known as lux, or lumens per square meter (1 lumen/m2 = 1 lux).

Blue light also works together with red light to help the plant “know” whether it’s day or night time, and help set circadian rhythms. You may notice that cannabis plants start drooping right before the lights go off each day, and they start perking up right when lights come on. This is a way for the plant to save energy while it’s “sleeping.” Since the blue in the light helps it “know” the time schedule, it will prepare as best it can for lights-out and lights-on.

There’s two main ways to increase the amount of light for your indoor plants:

Cannabis grow light spectrum

UVC rays are the most dangerous out of the three and they are not useful for both humans as well as marijuana plants.

Another benefit of adding green light to your color spectrum is that it does not trigger flowering in marijuana plants. This plant is extremely sensitive to light/dark cycles. Therefore, even small amounts of light during nighttime can trigger marijuana plants into thinking that it’s flowering time. As green light is invisible to cannabis, it is the perfect light color that you can use. That is if you wish to work on your cannabis plants during nighttime.

The light spectrum is a factor that cannot be ignored while you create an ideal environment for marijuana cultivation. Most growers have multiple goals like achieving high yields from their plants and increasing the THC levels. Improving and maintaining the overall health of their plants for indoor growing is crucial. Good growers need to involve in planning and coming up with technical solutions to achieve their goals. They should understand that adequate light is the one of important factors while growing marijuana plants. Colors of grow light are your secret weapon to produce more marijuana buds.

Grow light spectrum can be termed as electromagnetic wavelengths of light that are caused due to a light source and which promote plant growth. Plants use light in the photosynthetic active radiation (PAR) range of wavelengths (400 to 700nm) for photosynthesis.

UVB (280-315 nm)

First, you need to understand whether the color of light affects plant growth or not. The answer is yes, the color of light affects plant growth. However, it is distinctly notable under low light. The colors from the color spectrum that are most effective for the growth of plants are blue and red light. The colors like yellow and green are the least effective. Different colors should be used at different phases of plant growth. In the case of marijuana, blue light should be used during the vegetative stage. Red light is best when the plant starts entering the flowering stage and UV light helps in increasing THC levels in marijuana.

Cannabis is used for many medicinal and recreational purposes. Therefore, many states and countries have legalized its use and cultivation. Countries like the United States of America have allowed the growth of marijuana plants at home. Therefore, cannabis growers need to know about how will the colors of LED grow light affect the growth of their marijuana plants.

The energy emitted from the sun is in the form of radiation. The ozone layer filters this radiation and allows only wavelengths from 300-1100 nm to reach plants. This light is referred to as light spectrum, visible spectrum, or color spectrum. Its range is in between 380-750 nm approximately. A spectrum is a band of numerous colors namely red, orange, yellow, green, blue, indigo and violet.

Violet light for growing cannabis

Light is one of the most important factors in marijuana cultivation. Different spectrum colors have different roles in the development and growth of marijuana plants. Therefore, it is important to take care of the spectrum of grow light colors as they affect the growth of plants differently depending on environmental conditions. Normally, chlorophyll which converts light energy to chemical energy absorbs most of the light in red and blue light spectrums for photosynthesis. Therefore, both these lights are found at the top of the PAR range.

Violet grow lights colors wavelength ranges from 380 to 450 nm. It is the bottom end light of the visual light spectrum. The range of violet light is considered as it improves the taste of flowers. In addition, it is considered to improve the potency and color of the plants. However, violet light cannot be considered as a major growth factor when compared to the red and blue light spectrum.

Cannabis grow light spectrum

Many of the misconceptions about green light stem from how the human eye perceives green light. We easily perceive green light, but other colors, such as blue, are more difficult for us to see. Because so much of our environment (i.e., plant life) reflects green light, it’s adaptive for us to perceive green most readily.

Greenlight is subject to the most misconceptions. While many growers believe cannabis plants don’t utilize green light for photosynthesis, they actually do, and green light is important for other processes as well.

[3] Terashima, I. et al. Green Light Drives Leaf Photosynthesis More Efficiently than Red Light in Strong White Light: Revisiting the Enigmatic Question of Why Leaves are green. Plant and Cell Physiology. 2009.

The Benefits of Green Light for Cannabis

Another reason for green light’s exclusion from blue-red fixtures is a misinterpretation of laboratory studies. It’s well-documented that blue and red light are well-absorbed by plants and strongly drive photosynthesis. In fact, they’re the primary drivers of photosynthesis. The plant’s most abundant chlorophylls — chlorophyll a and chlorophyll b — absorbed and blue light.

Or, feel free to check out the other two parts of this three-part series:

Studies have shown again and again that cannabis plants use green light.[1] But green light is different from red or blue. It behaves differently in the canopy, and different photoreceptors use it for photosynthesis — not just chlorophyll a and chlorophyll b.

Green Light and LED Technology

Greenlight also signals plant morphology. It plays an important role in mediating a plant’s responses to blue light, and it influences leaf growth and early stem elongation. By sensing the ratio of light colors, plants can tell if they’re in shade or if they’re receiving direct light, and how to position their leaves to maximize light absorption throughout the day. That’s because green light penetrates leaves more easily than other colors. When plants sense a higher green-to-blue ratio, they assume they’re shaded by other plants, and they’re more likely to elongate their stems to compete.

Research by Heliospectra prompted the market’s adoption of broad-spectrum LED fixtures containing green wavelengths. Our early studies with white light and green-emitting LEDs confirmed what academics already knew: green light drives photosynthesis and plays other important roles.