• If you need help identifying a pepper, disease, or plant issue, please post in Identification.

Quantum Board Led Kelvin

honestly it probably doesn't matter. if you're vegging them out you might get a little more stretch on the 4000K, i've been growing a pepper at my work under a qb 65 that is 4k and it blooms and grows just fine. 3000k will probably keep the plants a little more compact.
 
thefish said:
honestly it probably doesn't matter. if you're vegging them out you might get a little more stretch on the 4000K, i've been growing a pepper at my work under a qb 65 that is 4k and it blooms and grows just fine. 3000k will probably keep the plants a little more compact.
Correct me if I'm wrong, but isn't that exactly the opposite of how the color spectrums work for plants? Blue light more towards the 6500K spectrum helps promote short stocky plants with tight internodal spacing, while lower spectrum, like 3000K normally helps with blooming... although full spectrum is generally recommended as the best route to go for peppers, which is somewhere between the 5000K and 6500K spectrums.

I've grown under 3000K before without issues, but I've been using 6500k for the last 9 years now.
 
U)<now said:
Correct me if I'm wrong, but isn't that exactly the opposite of how the color spectrums work for plants? Blue light more towards the 6500K spectrum helps promote short stocky plants with tight internodal spacing, while lower spectrum, like 3000K normally helps with blooming... although full spectrum is generally recommended as the best route to go for peppers, which is somewhere between the 5000K and 6500K spectrums.

I've grown under 3000K before without issues, but I've been using 6500k for the last 9 years now.
 
you aren't wrong- it is conventional wisdom but these are generalities based around growing plants with MH and HPS or Fluorescent based light sources which have spectrum that completely differ from these phosphor coated led chips. i get compact growth on multiple species of plants (peppers, orchids, epiphyllum and a multitude of other houseplants) using 3000k white LEDs. having the spectrum more blue especially if you only have one light source spread across an array of plants causes the plants to experience more phototropism towards the light and makes my plants contort towards the highest intensity light. stretch is also much more of a function of how far the plants are from the light source with these leds. before I got a QB 65 (3000k) for the ghost pepper im growing at my desk at work it was stretching like crazy under a much bluer 50w led array (5000k). the quality of light is just better from these chips. that is why I'm suggesting it probably doesn't matter much- the light produces a much more natural plant growth response compared to other light sources. this is just my experience working with these newer leds over the past year. 
 
Compare the relative blue intensity of HPS spectrum to 3000k quantum board. The HPS would be considered a warm, yellowish/red white light and probably is around 2700K color temp a 3000k QB on the other hand has 5x more relative blue intensity. At any spectrum QB you will get a more balanced spectrum with more blue light than traditional horticulture lighting units, stretch just wont be as big of a problem (plant genetics aside).
 
600-watt-hps-spectrum-analysis.jpg

 
QB288_388_spectrum_5328c697-3746-465d-8e1f-5bc9834e5378.png
 
Walchit said:
Well from the looks of those graphs, 4000k looks well rounded
 
keep in mind that red photons produce the highest amount of photosynthesis per photon as compared to cyan or blue so technically the 3000k spectrum has a greater portion the photons produced being used at the highest efficiency by the plant. anyways like i said you can grow with a 3000k or a 4000k just fine or you can get nerdy. this is why you'll notice that a lot of the newer leds coming out have a pink spectrum as they are taking advantage of the efficiency of red but providing enough blue for proper plant morphology.
 
Back
Top