My understanding is blue light lower on the spectrum needs to be less intense vs higher up on the spectrum red light needs to be more intense to achieve to desired effect.
Blue light tends to make plants short and compact. Red photons are just good for overall growth. They both contribute to PPFD that's hitting your plant.
Looking at the
QB2000 Spectrum its peak is blue light so I'm using it for veg.
QB2000 Driver
View attachment 5351342
Then flower under the
M320 Spectrum.
Any thoughts about the highest percentage to get up to on the QB 2000 within 6 weeks of seedling before going under M320 @ 50% intensity?
I run a veg light for seedlings at about 300µmols and then increase light as quickly as possible to the light saturation point which is 800-1000µmols for cannabis. More light increases crop yield and quality as long as the rest of the parameters of the grow are co-optimized. With that light, you should shoot to be at 100% by 6 weeks and that's running 24/0. At 4 weeks, 75% at 24/0.
Cannabis loves light. As long as your grow environment is good, turn it up to 11. Watch your plants for signs of light avoidance (tacoing or rotating the leave around the axis of the petiole). If you get that, drop your PPFD a bit. That happens to me fairly regularly grows because I give my plants lots of light.
Below are the light values on my 40± day old Glookie photoperiod plant.
That's a Growcraft X3 flower light running at 219 watts. The samples were taken at left rear, right rear, center rear, etc.
76 is the standard deviation for PPFD, 4 is the SD for DLI. Those numbers indicate it's a pretty even canopy. This strain seems to be a little more light sensitive than my other grows (I've only done five other grows). I got a little tacoing in the center so I had to back the wattage down from 238.
[checks out the light at the link]
You know, that looks like a really good light. When I saw the price, I was thinking "meh" but, wow, that's a great price for a really solid performer. Good choice!
Heh, lemme ask you - not a lot of growers used separate veg and flower lights. Why did you go that route? I use separate veg and flower lights but the market has moved strongly in the direction of white LED's so I'm wondering why you made that decision.
