Chlorophyll and Light:
Chlorophyll a and b are the products of photosynthesis. Chlorophyll
allows the plant to absorb the light, turning solar (light) energy into sugars
used as energy for plant growth.
Chlorophyll a has absorption peaks in the red range of 640 nanometers.
Chlorophyll b has absorption peaks in the blue range of 454 nanometers.
Plants have about twice as much chlorophyll a as they do chlorophyll b.
One would assume that a 2:1 ratio of red to blue light would be best
suited for plant growth. However, because of the blending of light and
other necessary pigments and carotenoids, a much higher ratio of red to
blue light has been shown to produce the best results. Current studies
show that the ratio of 8:1 or 7:2 red/blue is most effective.
Carotenoids are a group pigments which occur in all photosynthetic
organisms. Carotenoids work to protect the plant from light that may be
harmful to the plant. They absorb light maximally at wavelengths
between 460 and 550 nm and are therefore yellow, red or orange in
colour as they reflect the wavelengths in this part of the spectrum.
Carotenoids are found in all photosynthetic organisms.
Many "orange" spectrum lights are presently on the market because of
the purported effect to produce carotenoids. Testing has shown that the
orange spectrum lights provide no additional benefit to plants grown
exclusively under LEDs since the LED spectrum can be controlled to
eliminate the harmful light. Also, carotenoid absorption in the red
spectrum may be sufficient to provide the pigments necessary for
optimum plant growth.
Other pigments associated with the light harvesting machinery of plants
include xanthophylls, zeaxanthin, phycoerythrin, and phycocyanin.
These other pigments absorb light in the red and blue spectrum.
Chlorophyll a and b are the products of photosynthesis. Chlorophyll
allows the plant to absorb the light, turning solar (light) energy into sugars
used as energy for plant growth.
Chlorophyll a has absorption peaks in the red range of 640 nanometers.
Chlorophyll b has absorption peaks in the blue range of 454 nanometers.
Plants have about twice as much chlorophyll a as they do chlorophyll b.
One would assume that a 2:1 ratio of red to blue light would be best
suited for plant growth. However, because of the blending of light and
other necessary pigments and carotenoids, a much higher ratio of red to
blue light has been shown to produce the best results. Current studies
show that the ratio of 8:1 or 7:2 red/blue is most effective.
Carotenoids are a group pigments which occur in all photosynthetic
organisms. Carotenoids work to protect the plant from light that may be
harmful to the plant. They absorb light maximally at wavelengths
between 460 and 550 nm and are therefore yellow, red or orange in
colour as they reflect the wavelengths in this part of the spectrum.
Carotenoids are found in all photosynthetic organisms.
Many "orange" spectrum lights are presently on the market because of
the purported effect to produce carotenoids. Testing has shown that the
orange spectrum lights provide no additional benefit to plants grown
exclusively under LEDs since the LED spectrum can be controlled to
eliminate the harmful light. Also, carotenoid absorption in the red
spectrum may be sufficient to provide the pigments necessary for
optimum plant growth.
Other pigments associated with the light harvesting machinery of plants
include xanthophylls, zeaxanthin, phycoerythrin, and phycocyanin.
These other pigments absorb light in the red and blue spectrum.
LED, light emitting diode,
The technology began in the early twentieth century. Without getting into the chemical
composition involved in producing the diodes, LED's work when an electrical current passes
through a diode that generally looks like a tiny light bulb. Until recently, the use of LED's has
been limited by their cost. Lately, LED use has expanded as the cost to produce the diodes
has lowered and the long life and power saving properties of LED's make them a more
efficient alternative than other types of light.
Recently LED use has spread to the horticultural industry. Plants use light to produce the
sugars needed for growth. A basic equation is like this: light plus oxygen and water at the
roots along with nitrogen equals plant growth (certainly other elements and minerals are used
by plants but our focus is on the "light" aspect of the equation). The type of light needed by the
plant depends on the particular plant and its particular stage of growth. The quest has been to
produce the highest quality light for the individual plant at each of its stages of growth.
Many grow lights have been sold with the label "full-spectrum". The term is misleading for two
reasons. First, sunlight is the only true full spectrum light available. Second, plants do not
need a full spectrum and for most plants some parts of the spectrum can be harmful. For the
most part, plants need red and blue light.
Photosynthesis is most affected during the absorption of red and blue light. Light is
measured in by its wave length in nanometers. Red light in the range of 640 nanometers and
blue light in the range of 450 nanometers has the greatest effect on chlorophyll production.
LED technology lets us isolate the particular wavelength of light for maximum chlorophyll
production. Thus, growing under a LEDs one can maximize environmental control by giving
the plant the exact type of light most beneficial to plant growth.
Currently, the red/blue grow lights with a ratio of no less than 2:1 red/blue diodes seems most
effective. For flowering and fruiting plants a higher ratio as much as 10:1 red/blue seems to
produce the best results. The most productive all-around ratio shows that an 8:1 red/blue
ratio works best. While LEDs are best used as supplemental lighting (the same can be said
for all grow lights) in conjunction with sunlight. With or without supplemental sunlight, LEDs
outperform all other types of grow lights for their growing ability.
Several advantages:
* Longer life (up to ten times longer than its nearest competitor)
* Less heat generation (lower cooling costs and often a major factor in summer time indoor
growing projects)
* Isolated spectrum (save energy and eliminate harmful light)
* Lower power consumption with LED's using about four times less power than other types of
grow lights.
Other interesting facts about LEDs in the horticultural industry:
NASA is currently using LED's to grow plants in space. See:
http://www.nasa.gov/centers/marshall/news/news/releases/2003/03-199.html
Chlorophyll information:
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookPS.html
Whyleds.com offers product reviews, news and information on best sale prices for LED
selling products. Copyright, 2009, whyleds.com. All rights reserved.
The technology began in the early twentieth century. Without getting into the chemical
composition involved in producing the diodes, LED's work when an electrical current passes
through a diode that generally looks like a tiny light bulb. Until recently, the use of LED's has
been limited by their cost. Lately, LED use has expanded as the cost to produce the diodes
has lowered and the long life and power saving properties of LED's make them a more
efficient alternative than other types of light.
Recently LED use has spread to the horticultural industry. Plants use light to produce the
sugars needed for growth. A basic equation is like this: light plus oxygen and water at the
roots along with nitrogen equals plant growth (certainly other elements and minerals are used
by plants but our focus is on the "light" aspect of the equation). The type of light needed by the
plant depends on the particular plant and its particular stage of growth. The quest has been to
produce the highest quality light for the individual plant at each of its stages of growth.
Many grow lights have been sold with the label "full-spectrum". The term is misleading for two
reasons. First, sunlight is the only true full spectrum light available. Second, plants do not
need a full spectrum and for most plants some parts of the spectrum can be harmful. For the
most part, plants need red and blue light.
Photosynthesis is most affected during the absorption of red and blue light. Light is
measured in by its wave length in nanometers. Red light in the range of 640 nanometers and
blue light in the range of 450 nanometers has the greatest effect on chlorophyll production.
LED technology lets us isolate the particular wavelength of light for maximum chlorophyll
production. Thus, growing under a LEDs one can maximize environmental control by giving
the plant the exact type of light most beneficial to plant growth.
Currently, the red/blue grow lights with a ratio of no less than 2:1 red/blue diodes seems most
effective. For flowering and fruiting plants a higher ratio as much as 10:1 red/blue seems to
produce the best results. The most productive all-around ratio shows that an 8:1 red/blue
ratio works best. While LEDs are best used as supplemental lighting (the same can be said
for all grow lights) in conjunction with sunlight. With or without supplemental sunlight, LEDs
outperform all other types of grow lights for their growing ability.
Several advantages:
* Longer life (up to ten times longer than its nearest competitor)
* Less heat generation (lower cooling costs and often a major factor in summer time indoor
growing projects)
* Isolated spectrum (save energy and eliminate harmful light)
* Lower power consumption with LED's using about four times less power than other types of
grow lights.
Other interesting facts about LEDs in the horticultural industry:
NASA is currently using LED's to grow plants in space. See:
http://www.nasa.gov/centers/marshall/news/news/releases/2003/03-199.html
Chlorophyll information:
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookPS.html
Whyleds.com offers product reviews, news and information on best sale prices for LED
selling products. Copyright, 2009, whyleds.com. All rights reserved.
whyleds.com
Peppers and tomato seedlings growing
under a 120 watt LED
under a 120 watt LED
