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Drawbacks of LEDs

Posted by David Jones on

Demand for LEDs is at an all-time high, and they are being promoted as the eco-friendly lighting option. It is prudent to keep its drawbacks in mind, to understand how best one can use them in everyday life or as grow-lights in indoor plant cultivation. 

Lifespan of LEDs

The advertised claims are that LEDs can last up to 35,000 to 50,000 hours. This is significantly longer than its closest rival the eco-friendly compact fluorescent light (CFL), which last 10,000 to 15,000 hours, or the conventional incandescent bulbs which last only 1,000 to 2,000 hours. However, experience has shown, it is best to expect that LEDs only last 50% to 70% of the advertised lifespan (1). 

Even with these lower pragmatic expectations, LEDs outperform all other lighting systems. Moreover, though LEDs do not last the advertised 50,000 hours, unlike incandescent bulbs they do not burn out abruptly but gradually dim over time (2). 

LEDs are Expensive

This is cited as one of the main disadvantages of LEDs in comparison to other types of lights. It is true that currently, the initial capital cost of LEDs is much higher than that of many conventional lights, in terms of ‘price-per-lumen’ (1). 

However, because LEDs are seen as the light of the future, the innovations and development that this technology attracts, is making them increasingly more economical. These days they are offered at prices competitive with CFL (3). 

Moreover, LEDs have a much lower energy consumption compared to other lighting systems and result in considerable energy savings in their life-span. Given their relatively long life-span, they need to be replaced less often and result in lower maintenance costs in terms of material and labor. When all these factors are considered, LEDs are actually cheaper in the long run (2). 

Less Luminescent

LEDs are small, and even though they are highly efficient, each LED produces less number of lumens or brightness. So it is necessary to use many LEDs to get the same brightness as a single incandescent bulb. This is another reason why using LEDs becomes expensive (1, 2). 

LEDs’ ability to provide light without the accompanying heat that other lights do makes them the better option for many uses, compensating for this drawback. Moreover, as grow-lights, smaller light sources can be an advantage in combining different colors to achieve the correct light rendering for growing vegetables and flowers. 

Performance

Contrary to advertisements, LEDs’ performance depends on the ambient temperature of the atmosphere and age. 

Heat: LEDs produce heat at the semiconductor junction within the device, where 60 to 95% of the input power is lost as heat. Therefore, when the ambient temperatures rise, this can become a problem, as the LED characteristics, such as color, can change. In extreme circumstances, the damage can be permanent affecting the lifespan of the LEDs (1, 2). 

This is a factor which must be considered when using them in applications in the automobile, medical and military sectors. This is especially a concern when they have to operate in conditions where there are big differences in temperatures as in automobiles (1). 

This problem can be fixed through correct engineering of the light fixture. A heat sink which is a device with fins that conducts heat away from the LED can be used in a process called heat sinking to keep the LEDs cool (4). 

Age: In addition, LEDs change color due to age, and the perception of white LEDs is also not very consistent. 

Supply of electricity

Energy must be supplied at the correct voltage at a constant flow. This makes LEDs complex electronic devices requiring high levels of technical expertise during preparation. 

During operations, they need a series of resistors to maintain the flow of electricity (1, 2).

LEDs’ Toxicity

Though LEDs do not contain mercury like their conventional counterparts, they do contain many other dangerous heavy metals, such as lead, arsenic, nickel, and copper. Red LEDs are the worst offenders containing eight times the amount of lead allowed by Californian state laws. Lead is well known as a neurotoxin, and a carcinogenic. Arsenic can also lead to cancer and other problems, while nickel causes allergic reactions. Copper can harm aquatic animals and is an environmental threat (5). 

LEDs are at present not considered hazardous material by law. However, in their best interests and to be safe, people who clean up any broken LEDs should use gloves and mask, and treat the LEDs’ waste as well as the materials used for cleaning as hazardous waste. Similarly, in case of car crashes or broken traffic lights, places where they could be a high concentration of LEDs, people should take care by using protective garments and treating the waste as hazardous and dispose of it accordingly (3). 

The scientists who discovered the toxicity, have advised setting safe benchmarks for manufacturers to improve their design with safer materials. They also seek government engagement to motivate recyclers and waste management teams in adopting proper disposal methods for end-of-life LEDs (5).

Blue Light Hazard of LEDs

There is growing concern that cool white and blue LEDs could lead to blue-light-hazard, which is harmful to eyes. Blue light falls in the short wavelength and high energy part of the light spectrum. The human eye cannot filter out blue lights, so excessive exposure to blue light leads to eye strain, and could also lead to macular degeneration (6). 

However, there are many scientists who challenge the claim that LEDs emit enough blue light that could cause eye damage. However, even they advise that it is best not to expose people, especially babies, to cool white or blue lights. Instead, it would be best for people to consider the warm white light for fixtures at home and in buildings (7). 

People who are involved in the indoor cultivation of plants can use suitable eyeglasses, which filter out blue, to avoid any possible harm to their eyes as an occupational hazard (6). Some examples are, - special glare-reducing anti-reflective coatings for lenses. - glasses with photochromic lenses, which offer protection from blue light as well as UV radiation both indoors and outdoors.

It should also be remembered that blue light is not all bad, some of it is actually even beneficial for people. It is when the eyes are excessively exposed to blue light that it could become a problem (6).

In the Balance LEDs are Beneficial

There is growing concern that cool white and blue LEDs could lead to blue-light-hazard, which is harmful to eyes. Blue light falls in the short wavelength and high energy part of the light spectrum. The human eye cannot filter out blue lights, so excessive exposure to blue light leads to eye strain, and could also lead to macular degeneration (6). 

However, there are many scientists who challenge the claim that LEDs emit enough blue light that could cause eye damage. However, even they advise that it is best not to expose people, especially babies, to cool white or blue lights. Instead, it would be best for people to consider the warm white light for fixtures at home and in buildings (7). 

 

Read more

Drawbacks of LEDs

Posted by David Jones on

Demand for LEDs is at an all-time high, and they are being promoted as the eco-friendly lighting option. It is prudent to keep its drawbacks in mind, to understand how best one can use them in everyday life or as grow-lights in indoor plant cultivation. 

Lifespan of LEDs

The advertised claims are that LEDs can last up to 35,000 to 50,000 hours. This is significantly longer than its closest rival the eco-friendly compact fluorescent light (CFL), which last 10,000 to 15,000 hours, or the conventional incandescent bulbs which last only 1,000 to 2,000 hours. However, experience has shown, it is best to expect that LEDs only last 50% to 70% of the advertised lifespan (1). 

Even with these lower pragmatic expectations, LEDs outperform all other lighting systems. Moreover, though LEDs do not last the advertised 50,000 hours, unlike incandescent bulbs they do not burn out abruptly but gradually dim over time (2). 

LEDs are Expensive

This is cited as one of the main disadvantages of LEDs in comparison to other types of lights. It is true that currently, the initial capital cost of LEDs is much higher than that of many conventional lights, in terms of ‘price-per-lumen’ (1). 

However, because LEDs are seen as the light of the future, the innovations and development that this technology attracts, is making them increasingly more economical. These days they are offered at prices competitive with CFL (3). 

Moreover, LEDs have a much lower energy consumption compared to other lighting systems and result in considerable energy savings in their life-span. Given their relatively long life-span, they need to be replaced less often and result in lower maintenance costs in terms of material and labor. When all these factors are considered, LEDs are actually cheaper in the long run (2). 

Less Luminescent

LEDs are small, and even though they are highly efficient, each LED produces less number of lumens or brightness. So it is necessary to use many LEDs to get the same brightness as a single incandescent bulb. This is another reason why using LEDs becomes expensive (1, 2). 

LEDs’ ability to provide light without the accompanying heat that other lights do makes them the better option for many uses, compensating for this drawback. Moreover, as grow-lights, smaller light sources can be an advantage in combining different colors to achieve the correct light rendering for growing vegetables and flowers. 

Performance

Contrary to advertisements, LEDs’ performance depends on the ambient temperature of the atmosphere and age. 

Heat: LEDs produce heat at the semiconductor junction within the device, where 60 to 95% of the input power is lost as heat. Therefore, when the ambient temperatures rise, this can become a problem, as the LED characteristics, such as color, can change. In extreme circumstances, the damage can be permanent affecting the lifespan of the LEDs (1, 2). 

This is a factor which must be considered when using them in applications in the automobile, medical and military sectors. This is especially a concern when they have to operate in conditions where there are big differences in temperatures as in automobiles (1). 

This problem can be fixed through correct engineering of the light fixture. A heat sink which is a device with fins that conducts heat away from the LED can be used in a process called heat sinking to keep the LEDs cool (4). 

Age: In addition, LEDs change color due to age, and the perception of white LEDs is also not very consistent. 

Supply of electricity

Energy must be supplied at the correct voltage at a constant flow. This makes LEDs complex electronic devices requiring high levels of technical expertise during preparation. 

During operations, they need a series of resistors to maintain the flow of electricity (1, 2).

LEDs’ Toxicity

Though LEDs do not contain mercury like their conventional counterparts, they do contain many other dangerous heavy metals, such as lead, arsenic, nickel, and copper. Red LEDs are the worst offenders containing eight times the amount of lead allowed by Californian state laws. Lead is well known as a neurotoxin, and a carcinogenic. Arsenic can also lead to cancer and other problems, while nickel causes allergic reactions. Copper can harm aquatic animals and is an environmental threat (5). 

LEDs are at present not considered hazardous material by law. However, in their best interests and to be safe, people who clean up any broken LEDs should use gloves and mask, and treat the LEDs’ waste as well as the materials used for cleaning as hazardous waste. Similarly, in case of car crashes or broken traffic lights, places where they could be a high concentration of LEDs, people should take care by using protective garments and treating the waste as hazardous and dispose of it accordingly (3). 

The scientists who discovered the toxicity, have advised setting safe benchmarks for manufacturers to improve their design with safer materials. They also seek government engagement to motivate recyclers and waste management teams in adopting proper disposal methods for end-of-life LEDs (5).

Blue Light Hazard of LEDs

There is growing concern that cool white and blue LEDs could lead to blue-light-hazard, which is harmful to eyes. Blue light falls in the short wavelength and high energy part of the light spectrum. The human eye cannot filter out blue lights, so excessive exposure to blue light leads to eye strain, and could also lead to macular degeneration (6). 

However, there are many scientists who challenge the claim that LEDs emit enough blue light that could cause eye damage. However, even they advise that it is best not to expose people, especially babies, to cool white or blue lights. Instead, it would be best for people to consider the warm white light for fixtures at home and in buildings (7). 

People who are involved in the indoor cultivation of plants can use suitable eyeglasses, which filter out blue, to avoid any possible harm to their eyes as an occupational hazard (6). Some examples are, - special glare-reducing anti-reflective coatings for lenses. - glasses with photochromic lenses, which offer protection from blue light as well as UV radiation both indoors and outdoors.

It should also be remembered that blue light is not all bad, some of it is actually even beneficial for people. It is when the eyes are excessively exposed to blue light that it could become a problem (6).

In the Balance LEDs are Beneficial

There is growing concern that cool white and blue LEDs could lead to blue-light-hazard, which is harmful to eyes. Blue light falls in the short wavelength and high energy part of the light spectrum. The human eye cannot filter out blue lights, so excessive exposure to blue light leads to eye strain, and could also lead to macular degeneration (6). 

However, there are many scientists who challenge the claim that LEDs emit enough blue light that could cause eye damage. However, even they advise that it is best not to expose people, especially babies, to cool white or blue lights. Instead, it would be best for people to consider the warm white light for fixtures at home and in buildings (7). 

 

Read more


How Different Colored Lighting Affects Different Plants

Posted by David Jones on

The variety of green and flowering plants in this world assures that everyone can find something to their liking that grows in their climate zone and can thrive under the particular circumstances of their specific home. And there are definitely different purposes for each type of plant, from bearing edible fruits to herbs and spices, medical purposes, and even just plain and simple beauty. But one thing is true of all plants – they require light to grow.

Of course, in nature, plants get sunlight, which provides the full spectrum of color, so many plants grow strong without any special care. At the same time, advances in science and technology have proven that specific colors of light serve a variety of purposes when it comes to plant growth. Understanding these basics can improve the growth of your plants over time, utilizing particular colors of light during certain stages to help produce the largest plants with the greatest health and highest yield.

A Quick Lesson in Light

Sunlight appears 'white' until you push it through a prism. This refracts – or fractures – the light into its color spectrum, otherwise noted as the 'rainbow'. The rainbow, however, is the basic primary range of colors, with others that are invisible to the human eye – infrared on the low frequency or 'red' end and ultraviolet on the high frequency or 'purple' end of the spectrum.

 

Every object absorbs most colors, leaving it to appear as the color (or combination of colors) that it does not absorb. For instance, a red flower is red because it doesn͛'t absorb the red light but does absorb all other colors from the spectrum. Tree bark appears brown likely due to not absorbing red, blue, and purple. It would take a very specific degree to be able to explain this fully, but basically, everything manmade and natural has a color or colors that are not absorbed, and thus we have the beauty of the world around us.
But colors don't just work for beautification purposes. Most colors have a purpose when it comes to plants, as well. And when you enter into horticultural, it can be extremely beneficial to know how every color of the spectrum will affect your plants and their growth so that you can put into practice a certain regimen and get the best results.

Why Are Plants Green?

As discussed, every object has specific colors that it does not absorb. Plants typically do not absorb green light from the spectrum, which causes the leaves and stems to appear green. While this is likely due to the chlorophyll produced in the process known as photosynthesis, it seems that chlorophyll does not absorb green.

Photosynthesis

Photosynthesis is the process plants use to create their own food for growth. Using light, they go through a process that creates sugar on which they feed, causing them to grow. During the process, plants utilize a combination of chlorophyll, light, and water to create food that has a green pigment, leading to their coloration, and generate the air that we breathe. It's a digestive process, much like all organisms have, with its own special configuration, and plants can grow stronger and fuller with specific types of light provided at the right stages of growth.

Ultraviolet Light

Ultraviolet light(UV rays) is what activates pigment in our skin, causing us to tan. However, it's also detrimental to our health, leading to sunburn and shown to cause cancer. It's essential to realize that plants have weaknesses as well, and ultraviolet light, which is at such a high frequency it's invisible to the human eye, can damage plants in high quantities.

 

Of course, it has its uses, and you shouldn't deny your plants ultraviolet light. In fact, this part of the spectrum can actually cause your plants to produce anthocyan, a purplish substance that not only helps to protect your plants from damage due to UV light but also from detrimental micro-organisms.

 

However, you should carefully balance the amount of UV light your plants receive, as too much ultraviolet light can damage the plant DNA, its membranes, and its process of photosynthesis.

Far-Red or Infrared Light

At the other end of the spectrum is the invisible infrared light that we feel as heat on our skin. This is an interesting part of the spectrum in terms of its relationship to plants and growth. Unlike visible red light, plants reflect infrared light, which means that, when there is a high concentration of plants in a particular area, there is little infrared light available.

Plants use this to sense the density of plant population where they grow, which affects germination, or seed production. In fact, low levels of infrared light cause plants to 'pause' the germination process, noting that there is already a large population, and therefore, will not produce seeds under such conditions.
When this happens, you'll find that plants grow quickly, striving to outgrow their neighbors so they can reach above and gather more of the necessary light colors that help fuel the process of photosynthesis. However, this rapid growth in a competitive space can lead to your plants being weaker, with fewer flowers or fruit. In order to avoid this, you shouldn't use traditional incandescent light bulbs for plant growth, since they produce a great deal of infrared light and are not suitable for a high yield product.

Colors That Don't Matter

While use of green light with red can be productive, exclusively green light will do little for plants. This is because plants can only utilize colors to which they are sensitive, or for which they have receptors. These receptors – known as photoreceptors – are specific to colors in the spectrum and are found in the cells of plants, each one a pigment that is receptive of a certain color of light. Think of them as eyes that can only see one color and ignore all others in the spectrum.

Without photoreceptors for green light, there isn't much this color can do on its own for plant growth and production, but consider using it in combination with red light, which is essential during several stages of plant growth. On its own, green light will produce extremely weak vegetation that cannot survive to grow old and fruitful.

Yellow light also has no impact on plant growth, since plants do not absorb yellow light. In fact, a high concentration of yellow lighting, especially in the absence of more beneficial colors, can lead to slow growth or even the prevention of any growth.

While orange light doesn't have an effect on its own, plants tend to perceive it as red light and use it in the same manner. Violet and 'indigo' light are also colors that are absorbed and identified differently, typically seen by plants as blue light, another very important color of the spectrum for plant growth.

Red Light

Plants absorb red light through photoreceptors known as phytochromes, which are pigment that is blue-green in color. Red is perhaps the most vital of colors for all plants to receive in large quantities, since it is essential for size and important to the process of photosynthesis. 
Some of the areas in which red light are necessary include: 

 Hormone production – High levels of red light received during early growth produces meta-topolin, a hormone that prevents the breakdown of chlorophyll. This is precisely what a young 
plant needs to grow larger and stronger, since the chlorophyll is necessary in the process of 
photosynthesis in order to create adequate food (sugars) for the plant as it grows. The excess 
chlorophyll also keeps the plant very green, providing its health during this period. 
 Flowering and germination – Plants 'compare' the amount of red light to the amount of infrared light to determine if it should germinate or flower. If your plants are exposed to excess red light during the 'dark' period, you'll find that you'll have to wait longer to harvest from it, which is definitely not ideal. This is especially true of cannabis, which is part of the reason you'll find it ill-advised to enter the growing space during dark periods. 
 Seed type – Most growers want to produce female seeds (where applicable). While red light is incredibly important to the growth process, you don't want overexposure because too much red light can cause most seeds to grow into male seeds. 
 Flavor – For leafy greens, microgreens, herbs, and cannabis, you'll want to control the amount of red light based on the flavor you want to produce. Large amounts of red light produce larger amounts of certain oils, which can create a specific taste, usually causing
more bitterness in the flavor. While this may be desired in some plants, others will be less desirable. Determine your needs based on the types of plants you're growing.

Blue Light

Much like red light, plants have photoreceptors for blue light, called cryptochromes. As with red light, plants thrive with a good quantity of blue light, though exposure should be calculated differently during various stages of growth. For example, larger amounts of blue light may be beneficial during early stages of growth, as well as during the more 'dormant' periods of plant growth. Consider the following benefits of blue light on plants: 

 Hormone production – While red light produces a hormone that helps with photosynthesis, blue light decreases production of auxin. Auxin controls the growth of the stem as well as controlling the process of apical dominance, or the way a plant controls growth points and keeps buds from intertwining and creating a mess of excess branches. The overall effect of dampening auxin operation is that plants remain shorter and grow thicker and wider, which is 
what you want for sturdiness in the early growth stages. 
 Increased metabolism – The amount of blue light available to a plant determines how far the stomas – or pores in the epidermis or skin of the plant – open. These pores are used to take in carbon dioxide and release oxygen. With more blue light, the stomas are opened wider, which increases the metabolism of the plant, thereby accelerating growth and production. This is important during the flowering stage, creating more buds or flowers for harvest. 
 Growth direction – Blue light attracts plants, so you'll find that wherever the blue light is 
located, your plants 'reach' for it. This can help you assure that your plants are growing 'up'
in the direction you desire. 
 Multiplication and production – Leafy greens will be leafier, and all green will grow thicker with leaves when using the correct amount of blue light. In addition, when producing seeds, blue light will greatly increase your output (and support the output of female seeds where applicable and desirable). You'll find that, when you are lacking in blue light, you reap about 20 percent less in your harvest. This can be detrimental for herbs and especially for cannabis.

The Right Balance

While it is important to balance the full spectrum of light you use for plant growth, making sure you have the correct balance between the most vital colors – blue and red – will lead to the greatest production and healthiest plants. Typically, a 5:1 ratio of red light to blue will create sturdy, productive, mature plants that will germinate properly and produce an excellent crop for harvest. They will grow tall as well as thick, and you'll be able to keep them blooming and fruitful for a great many years. 

Read more

How Different Colored Lighting Affects Different Plants

Posted by David Jones on

The variety of green and flowering plants in this world assures that everyone can find something to their liking that grows in their climate zone and can thrive under the particular circumstances of their specific home. And there are definitely different purposes for each type of plant, from bearing edible fruits to herbs and spices, medical purposes, and even just plain and simple beauty. But one thing is true of all plants – they require light to grow.

Of course, in nature, plants get sunlight, which provides the full spectrum of color, so many plants grow strong without any special care. At the same time, advances in science and technology have proven that specific colors of light serve a variety of purposes when it comes to plant growth. Understanding these basics can improve the growth of your plants over time, utilizing particular colors of light during certain stages to help produce the largest plants with the greatest health and highest yield.

A Quick Lesson in Light

Sunlight appears 'white' until you push it through a prism. This refracts – or fractures – the light into its color spectrum, otherwise noted as the 'rainbow'. The rainbow, however, is the basic primary range of colors, with others that are invisible to the human eye – infrared on the low frequency or 'red' end and ultraviolet on the high frequency or 'purple' end of the spectrum.

 

Every object absorbs most colors, leaving it to appear as the color (or combination of colors) that it does not absorb. For instance, a red flower is red because it doesn͛'t absorb the red light but does absorb all other colors from the spectrum. Tree bark appears brown likely due to not absorbing red, blue, and purple. It would take a very specific degree to be able to explain this fully, but basically, everything manmade and natural has a color or colors that are not absorbed, and thus we have the beauty of the world around us.
But colors don't just work for beautification purposes. Most colors have a purpose when it comes to plants, as well. And when you enter into horticultural, it can be extremely beneficial to know how every color of the spectrum will affect your plants and their growth so that you can put into practice a certain regimen and get the best results.

Why Are Plants Green?

As discussed, every object has specific colors that it does not absorb. Plants typically do not absorb green light from the spectrum, which causes the leaves and stems to appear green. While this is likely due to the chlorophyll produced in the process known as photosynthesis, it seems that chlorophyll does not absorb green.

Photosynthesis

Photosynthesis is the process plants use to create their own food for growth. Using light, they go through a process that creates sugar on which they feed, causing them to grow. During the process, plants utilize a combination of chlorophyll, light, and water to create food that has a green pigment, leading to their coloration, and generate the air that we breathe. It's a digestive process, much like all organisms have, with its own special configuration, and plants can grow stronger and fuller with specific types of light provided at the right stages of growth.

Ultraviolet Light

Ultraviolet light(UV rays) is what activates pigment in our skin, causing us to tan. However, it's also detrimental to our health, leading to sunburn and shown to cause cancer. It's essential to realize that plants have weaknesses as well, and ultraviolet light, which is at such a high frequency it's invisible to the human eye, can damage plants in high quantities.

 

Of course, it has its uses, and you shouldn't deny your plants ultraviolet light. In fact, this part of the spectrum can actually cause your plants to produce anthocyan, a purplish substance that not only helps to protect your plants from damage due to UV light but also from detrimental micro-organisms.

 

However, you should carefully balance the amount of UV light your plants receive, as too much ultraviolet light can damage the plant DNA, its membranes, and its process of photosynthesis.

Far-Red or Infrared Light

At the other end of the spectrum is the invisible infrared light that we feel as heat on our skin. This is an interesting part of the spectrum in terms of its relationship to plants and growth. Unlike visible red light, plants reflect infrared light, which means that, when there is a high concentration of plants in a particular area, there is little infrared light available.

Plants use this to sense the density of plant population where they grow, which affects germination, or seed production. In fact, low levels of infrared light cause plants to 'pause' the germination process, noting that there is already a large population, and therefore, will not produce seeds under such conditions.
When this happens, you'll find that plants grow quickly, striving to outgrow their neighbors so they can reach above and gather more of the necessary light colors that help fuel the process of photosynthesis. However, this rapid growth in a competitive space can lead to your plants being weaker, with fewer flowers or fruit. In order to avoid this, you shouldn't use traditional incandescent light bulbs for plant growth, since they produce a great deal of infrared light and are not suitable for a high yield product.

Colors That Don't Matter

While use of green light with red can be productive, exclusively green light will do little for plants. This is because plants can only utilize colors to which they are sensitive, or for which they have receptors. These receptors – known as photoreceptors – are specific to colors in the spectrum and are found in the cells of plants, each one a pigment that is receptive of a certain color of light. Think of them as eyes that can only see one color and ignore all others in the spectrum.

Without photoreceptors for green light, there isn't much this color can do on its own for plant growth and production, but consider using it in combination with red light, which is essential during several stages of plant growth. On its own, green light will produce extremely weak vegetation that cannot survive to grow old and fruitful.

Yellow light also has no impact on plant growth, since plants do not absorb yellow light. In fact, a high concentration of yellow lighting, especially in the absence of more beneficial colors, can lead to slow growth or even the prevention of any growth.

While orange light doesn't have an effect on its own, plants tend to perceive it as red light and use it in the same manner. Violet and 'indigo' light are also colors that are absorbed and identified differently, typically seen by plants as blue light, another very important color of the spectrum for plant growth.

Red Light

Plants absorb red light through photoreceptors known as phytochromes, which are pigment that is blue-green in color. Red is perhaps the most vital of colors for all plants to receive in large quantities, since it is essential for size and important to the process of photosynthesis. 
Some of the areas in which red light are necessary include: 

 Hormone production – High levels of red light received during early growth produces meta-topolin, a hormone that prevents the breakdown of chlorophyll. This is precisely what a young 
plant needs to grow larger and stronger, since the chlorophyll is necessary in the process of 
photosynthesis in order to create adequate food (sugars) for the plant as it grows. The excess 
chlorophyll also keeps the plant very green, providing its health during this period. 
 Flowering and germination – Plants 'compare' the amount of red light to the amount of infrared light to determine if it should germinate or flower. If your plants are exposed to excess red light during the 'dark' period, you'll find that you'll have to wait longer to harvest from it, which is definitely not ideal. This is especially true of cannabis, which is part of the reason you'll find it ill-advised to enter the growing space during dark periods. 
 Seed type – Most growers want to produce female seeds (where applicable). While red light is incredibly important to the growth process, you don't want overexposure because too much red light can cause most seeds to grow into male seeds. 
 Flavor – For leafy greens, microgreens, herbs, and cannabis, you'll want to control the amount of red light based on the flavor you want to produce. Large amounts of red light produce larger amounts of certain oils, which can create a specific taste, usually causing
more bitterness in the flavor. While this may be desired in some plants, others will be less desirable. Determine your needs based on the types of plants you're growing.

Blue Light

Much like red light, plants have photoreceptors for blue light, called cryptochromes. As with red light, plants thrive with a good quantity of blue light, though exposure should be calculated differently during various stages of growth. For example, larger amounts of blue light may be beneficial during early stages of growth, as well as during the more 'dormant' periods of plant growth. Consider the following benefits of blue light on plants: 

 Hormone production – While red light produces a hormone that helps with photosynthesis, blue light decreases production of auxin. Auxin controls the growth of the stem as well as controlling the process of apical dominance, or the way a plant controls growth points and keeps buds from intertwining and creating a mess of excess branches. The overall effect of dampening auxin operation is that plants remain shorter and grow thicker and wider, which is 
what you want for sturdiness in the early growth stages. 
 Increased metabolism – The amount of blue light available to a plant determines how far the stomas – or pores in the epidermis or skin of the plant – open. These pores are used to take in carbon dioxide and release oxygen. With more blue light, the stomas are opened wider, which increases the metabolism of the plant, thereby accelerating growth and production. This is important during the flowering stage, creating more buds or flowers for harvest. 
 Growth direction – Blue light attracts plants, so you'll find that wherever the blue light is 
located, your plants 'reach' for it. This can help you assure that your plants are growing 'up'
in the direction you desire. 
 Multiplication and production – Leafy greens will be leafier, and all green will grow thicker with leaves when using the correct amount of blue light. In addition, when producing seeds, blue light will greatly increase your output (and support the output of female seeds where applicable and desirable). You'll find that, when you are lacking in blue light, you reap about 20 percent less in your harvest. This can be detrimental for herbs and especially for cannabis.

The Right Balance

While it is important to balance the full spectrum of light you use for plant growth, making sure you have the correct balance between the most vital colors – blue and red – will lead to the greatest production and healthiest plants. Typically, a 5:1 ratio of red light to blue will create sturdy, productive, mature plants that will germinate properly and produce an excellent crop for harvest. They will grow tall as well as thick, and you'll be able to keep them blooming and fruitful for a great many years. 

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