I am new to the led world and so far it looks very promising. From what I have read, led lights target an exact nanometer and/or target specific kelvins (white light). Cannabis has a need for full spectrum light, tho this need may be small in comparison to reds and blues but it still needs it. So clearly a full spectrum led or one that has a tunable (intensity controll for targeted k or nm) would be the best choice.
[h=3]From Wikipedia, the free encyclopedia:
An action spectrum is the rate of a physiological activity plotted against wavelength of light. It shows which wavelength of light is most effectively used in a specific chemical reaction. Some reactants are able to use specific wavelengths of light more effectively to complete their reactions. For example, chlorophyll is much more efficient at using the red and blue spectrums of light to carry out photosynthesis. Therefore, the action spectrum graph would show spikes above the wavelengths representing the colors red and blue.[/h]The following action spectrum graph for chlorophyll production is overlaid upon the color wavelength spectrum, the corresponding spectrums generated by standard 80% Red/ 20% Blue LED Grow Lights and standard HID (Metal Halide) Grow Lights are also overlaid.
LED Grow Lights, used for this example, more closely parallel the exact wavelength requirements for chlorophyll producing plants, although most produce an excess of Red and are somewhat deficient in Blue light. By generating a light spectrum that most closely matches the Action Spectrum yields the greatest results with the least amount of energy expended.
The Standard Spectrum light include 10% 3500K White to fill in the requirements in the trough in the yellow and green zones.
Understanding General Spectrum Information:
200 - 280 nm UVC ultraviolet range which is generally harmful to plants. LEDs in this spectrum are non-existent or very expensive.
280 - 315 nm Includes harmful UVB ultraviolet light which causes plants colors to fade. This range is useful for Trichrome production, believed to be due to positive stress.
315 - 380 nm UVA ultraviolet light which is neither harmful nor beneficial to most plants.
380 - 400 nm Start of visible light spectrum. Process of chlorophyll absorption begins. UV protected plastics ideally block out any light below this range.
400 - 520 nm The violet, blue, and green bands. Peak absorption by chlorophyll occurs, and a strong influence on photosynthesis. (promotes vegetative growth)
520 - 610 nm The green, yellow, and orange bands and has less absorption by pigments.
610 - 720 nm The red band. Large amount of absorption by chlorophyll occurs, and most significant influence on photosynthesis. (promotes flowering and budding)
In Sunlight the ratio of red (660nm) to far red (730nm) is about 1.2:1
Interestingly Phytochrome Pfr is activated by 660nm and Pr is activated by 730nm.
720 - 1000 nm Little absorption by Chlorophyll here, Phytochrome responds in the 720range. Flowering and germination is influenced. Near this range and higher end of the band is the Infrared spectrum, which is mostly heat and promotes elongation or negatively affect water absorption/transpiration.
Many plant pigments have dual wavelength peaks that can be activated with LED light combinations:
Beta-carotene 450nm 480-485nm dual peak
chlorophyll a 430nm 662nm dual peak
chlorophyll b 453nm 642nm dual peak
phycoerythrin 590nm single peak
phycocyanin 625nm single peak
670nm and 700nm for the Emerson effect.
It is my understanding that cannabis has several "trigger banks" that innitate flowering.
Bank 2- is 630nm this is what triggers the plant to flower.
Bank 1- is 610nm and this is what triggers flowering after Bank 2
Bank 3- is 660nm and this is the one that gives you huge buds.
There are more banks for flowering that I am not totally clear on, but basically if you can provide all of them, a bumper crop is sure to reward you.
My question is:since plants have various peak requirments for specific wavelengths at different stages of growth. If you were to supply full spectrum (350-740) lets say each wavelength is at the same intensity- 100%. Theoretically the plants will only use what they need and disregard the rest past its peak of production, so could you veg and flower under the same constant intense light, without lessening your blues or going with a 7-1-1 ratio to flower.
Someone please with led experence chime in and correct me.
PEACE-DUCKEE
[h=3]From Wikipedia, the free encyclopedia:
An action spectrum is the rate of a physiological activity plotted against wavelength of light. It shows which wavelength of light is most effectively used in a specific chemical reaction. Some reactants are able to use specific wavelengths of light more effectively to complete their reactions. For example, chlorophyll is much more efficient at using the red and blue spectrums of light to carry out photosynthesis. Therefore, the action spectrum graph would show spikes above the wavelengths representing the colors red and blue.[/h]The following action spectrum graph for chlorophyll production is overlaid upon the color wavelength spectrum, the corresponding spectrums generated by standard 80% Red/ 20% Blue LED Grow Lights and standard HID (Metal Halide) Grow Lights are also overlaid.
One can observe that the standard HID Light produces light spectrums that are insufficient in the blue and red spectrum and excessive in the yellow-orange spectrum as well as in the yellow and green spectrum, where very little is absorbed. Halide lights compensate for this by producing bulk amounts in all spectrums they produce.LED Grow Lights, used for this example, more closely parallel the exact wavelength requirements for chlorophyll producing plants, although most produce an excess of Red and are somewhat deficient in Blue light. By generating a light spectrum that most closely matches the Action Spectrum yields the greatest results with the least amount of energy expended.
The Standard Spectrum light include 10% 3500K White to fill in the requirements in the trough in the yellow and green zones.
Understanding General Spectrum Information:
200 - 280 nm UVC ultraviolet range which is generally harmful to plants. LEDs in this spectrum are non-existent or very expensive.
280 - 315 nm Includes harmful UVB ultraviolet light which causes plants colors to fade. This range is useful for Trichrome production, believed to be due to positive stress.
315 - 380 nm UVA ultraviolet light which is neither harmful nor beneficial to most plants.
380 - 400 nm Start of visible light spectrum. Process of chlorophyll absorption begins. UV protected plastics ideally block out any light below this range.
400 - 520 nm The violet, blue, and green bands. Peak absorption by chlorophyll occurs, and a strong influence on photosynthesis. (promotes vegetative growth)
520 - 610 nm The green, yellow, and orange bands and has less absorption by pigments.
610 - 720 nm The red band. Large amount of absorption by chlorophyll occurs, and most significant influence on photosynthesis. (promotes flowering and budding)
In Sunlight the ratio of red (660nm) to far red (730nm) is about 1.2:1
Interestingly Phytochrome Pfr is activated by 660nm and Pr is activated by 730nm.
720 - 1000 nm Little absorption by Chlorophyll here, Phytochrome responds in the 720range. Flowering and germination is influenced. Near this range and higher end of the band is the Infrared spectrum, which is mostly heat and promotes elongation or negatively affect water absorption/transpiration.
Many plant pigments have dual wavelength peaks that can be activated with LED light combinations:
Beta-carotene 450nm 480-485nm dual peak
chlorophyll a 430nm 662nm dual peak
chlorophyll b 453nm 642nm dual peak
phycoerythrin 590nm single peak
phycocyanin 625nm single peak
670nm and 700nm for the Emerson effect.
It is my understanding that cannabis has several "trigger banks" that innitate flowering.
Bank 2- is 630nm this is what triggers the plant to flower.
Bank 1- is 610nm and this is what triggers flowering after Bank 2
Bank 3- is 660nm and this is the one that gives you huge buds.
There are more banks for flowering that I am not totally clear on, but basically if you can provide all of them, a bumper crop is sure to reward you.
My question is:since plants have various peak requirments for specific wavelengths at different stages of growth. If you were to supply full spectrum (350-740) lets say each wavelength is at the same intensity- 100%. Theoretically the plants will only use what they need and disregard the rest past its peak of production, so could you veg and flower under the same constant intense light, without lessening your blues or going with a 7-1-1 ratio to flower.
Someone please with led experence chime in and correct me.
PEACE-DUCKEE