LED Light Spectrum Question

[Upstate_indoor]

Amateur hour question here about LED light spectrum. My light has a blue/red switch they label as Veg/Flower which I took to mean "use this one, then this one" kind of settings. I was recently reading an article that did a study with lettuce that showed just blues to stunt growth horribly and it said to run both unless you want to save electricity at the cost of better growth. Anyone have experience or advice on if its better to run both, or switch between them?

I'll put a link the light below

https://www.amazon.com/gp/aw/d/B01MT2SGER?psc=1&ref=ppx_pop_mob_b_asin_title

 

[Drownomatic]

I would check how much PPFD it puts out in each mode, and with both on, and decide by total amount of light needed.

Remember to use the correct color calibration for the meter app

 

[Upstate_indoor]

I would check how much PPFD it puts out in each mode, and with both on, and decide by total amount of light needed.

Remember to use the correct color calibration for the meter app

I was thinking more along the lines of red and blue light triggering different kinds of growth. I've read a lot of conflicting reports

 

[Bill.de.Cat]

Quick web search..
Red Light for growing cannabis

Red light is the most effective spectrum light that encourages photosynthesis. This is because it is highly absorbed by the chlorophyll pigments. Its wavelength ranges from 620 to 750 nm. This light is essential during the flowering stage of the marijuana plants. Adding red light promotes budding and flowering. Many marijuana growers switch to strong red lights with more intensity once their plant has reached the flowering or budding stage. When red light paired with blue light can balance out any overstretching or disfigured elongation of stems. Red light and blue light together produce the best response from marijuana plants.

Blue light for growing cannabis

The blue light spectrum is very important for marijuana plant growth. It is mainly responsible for increasing plant quality. During the vegetative stage of growing marijuana, you should aim for growing leaves as many as possible. The blue grow lights colors wavelength is from 450 to 490 nm. Indoor growers use T5 or T8 lighting fixtures, CFLs (compact fluorescent lamps), or metal halide bulbs that have a blue band of light. They use these for the first few weeks to achieve desired goals. When marijuana plants grow outdoors the angle of the sun during spring allows blue light energy which is abundant in this season to penetrate the leaves. Therefore, this blue light signals the plants to grow healthy and large leaves and to become strong. The plants that are deficient in blue light generally turn out yellow or pale and are weak and flopping. Blue light is essential for young plants and seedlings in vegetative stages to properly grow roots and stems.

 

[Upstate_indoor]

Quick web search..
Red Light for growing cannabis

Red light is the most effective spectrum light that encourages photosynthesis. This is because it is highly absorbed by the chlorophyll pigments. Its wavelength ranges from 620 to 750 nm. This light is essential during the flowering stage of the marijuana plants. Adding red light promotes budding and flowering. Many marijuana growers switch to strong red lights with more intensity once their plant has reached the flowering or budding stage. When red light paired with blue light can balance out any overstretching or disfigured elongation of stems. Red light and blue light together produce the best response from marijuana plants.

Blue light for growing cannabis

The blue light spectrum is very important for marijuana plant growth. It is mainly responsible for increasing plant quality. During the vegetative stage of growing marijuana, you should aim for growing leaves as many as possible. The blue grow lights colors wavelength is from 450 to 490 nm. Indoor growers use T5 or T8 lighting fixtures, CFLs (compact fluorescent lamps), or metal halide bulbs that have a blue band of light. They use these for the first few weeks to achieve desired goals. When marijuana plants grow outdoors the angle of the sun during spring allows blue light energy which is abundant in this season to penetrate the leaves. Therefore, this blue light signals the plants to grow healthy and large leaves and to become strong. The plants that are deficient in blue light generally turn out yellow or pale and are weak and flopping. Blue light is essential for young plants and seedlings in vegetative stages to properly grow roots and stems.

Thank you, I've read similar things doing Google searches but also just as many contradictory articles: use blue lights only in seedling and veg then switch to strong reds only for pre-flower and flower, run blue and reds the whole time, etc. Each article has its own set of cons as well, such as some say that blue light only will stunt growth and cause small leaves, others saying mixing red into the blue before flowering will cause the plants to stretch, etc. Google searches are easy, the issue is that no two sources will agree on anything to do with growing other than light cycle (and thats even a contested topic with indoor autos.) Thats why I asked in a forum, to see if anyone had an opinion based on their experience and I know there is a lot of experience here.

 

[Bill.de.Cat]

Thank you, I've read similar things doing Google searches but also just as many contradictory articles: use blue lights only in seedling and veg then switch to strong reds only for pre-flower and flower, run blue and reds the whole time, etc. Each article has its own set of cons as well, such as some say that blue light only will stunt growth and cause small leaves, others saying mixing red into the blue before flowering will cause the plants to stretch, etc. Google searches are easy, the issue is that no two sources will agree on anything to do with growing other than light cycle (and thats even a contested topic with indoor autos.) Thats why I asked in a forum, to see if anyone had an opinion based on their experience and I know there is a lot of experience here.

I know years ago we'd run Metal Halide for veg and High Pressure Sodium for flower... Blue-MH, red-HPS

 

[Upstate_indoor]

I know years ago we'd run Metal Halide for veg and High Pressure Sodium for flower... Blue-MH, red-HPS

That makes sense, I think an issue I'm having is using LEDs is fairly new, not to mention using full spectrum LEDs. I think a lot of the seasoned growers use the tried and true methods like HPS so half of what I'm researching are methods still being developed.

 

[Bill.de.Cat]

That makes sense, I think an issue I'm having is using LEDs is fairly new, not to mention using full spectrum LEDs. I think a lot of the seasoned growers use the tried and true methods like HPS so half of what I'm researching are methods still being developed.

Oh I'm totally on LED now...3 x ts1000 from Mars Hydro..... I was talking about in the 80s when I grew before....HIDs were all we had back then

 

[Upstate_indoor]

Oh I'm totally on LED now...3 x ts1000 from Mars Hydro..... I was talking about in the 80s when I grew before....HIDs were all we had back then

That was before my day (by my day, I mean starting a few weeks ago lol.) But I think I'll leave both on a bit and just see what happens. This grow is more to learn and refine my equipment than to produce top shelf flowers. I already shocked them so why not? These pics are 4 weeks in from starting germination and grown under just the veg blues. They're a little rough but hanging in while I learn.

 

[Death The Cultivator]

Amateur hour question here about LED light spectrum. My light has a blue/red switch they label as Veg/Flower which I took to mean "use this one, then this one" kind of settings. I was recently reading an article that did a study with lettuce that showed just blues to stunt growth horribly and it said to run both unless you want to save electricity at the cost of better growth. Anyone have experience or advice on if its better to run both, or switch between them?

I'll put a link the light below

https://www.amazon.com/gp/aw/d/B01MT2SGER?psc=1&ref=ppx_pop_mob_b_asin_title

The main issue is that you are not dealing with a full spectrum 400-700nm light. Current LEDs typically use Nichia, Samsung, Bridgelux, etc. That entire page is dubious from the wattage to the spectrum claims. That is a blurple using narrow bands of red and blue. Good LEDs will have a kelvin 3000-5000k, a CRI 80-98, a ppfd map, testing info and so on. Look at horticulture lighting group.

You're probably best off turning on the Bloom and Veg spectrums together. A lot of blue without red will stunt but a full spectrum light would have a balance between 400-700nm optimizing plant growth. All around lights for veg and bloom will be around 3500k whereas flower lights are 2700-3100k with veg being 4000-5000k. 5000k would be detrimental to cannabis but not to basil.

Have you watched anything by Bruce Bugbee?

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