Lenin1917
Well-Known Member
They look good ngl, try it with something more sativa leaning next to a clone under mh. Not saying you’ll prefer it, just that there’s a very noticeable difference.
What to do if you have light stress in week 5 of bloom?
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PJ Diaz
Well-Known Member
I've grown with HPS, MH, CMH, and LED of various color temps. My experience shows that color temp does affect plant morphology. More specifically the effect as a result of the ratio between red and blue light makes a big difference, the colors in the middle not so much. Keep in mind that Kelvin is an average of all the colors, and doesn't really tell us the ratio of red to blue light. As an example, as 3000k HID light is going to have a substantially different color spectrum from a 3000k LED light.
PJ Diaz
Well-Known Member
The amount of stretch you might see under different types of light is also strain dependent. If I'm growing a short stocky plant, I will want to veg it under HPS just to get a bit more elongation from it. On the flip side, if it's a tall stretchy strain, I'd want to veg with MH.
Markshomegrown
Well-Known Member
I have always gone for short stocky plant(strains) don't see the point of growing a tall stretchy strain.
Markshomegrown
Well-Known Member
So if you where keeping the same plant going(clones) you could change the ratio of red to blue, this would control the stretch in theory but growing from seed, wouldn't know if 2700k or 3500k is the best light?
Markshomegrown
Well-Known Member
Every plant from seed is different, even from a pack of seeds, how much would LEDS reduced the stretch, you will never know.I just grew out some fogdog autos under mostly hps and other peoples under led were not so tall, mine hit 5’6 and a top hit the bulb got burnt
fire ass weed though
Northeastskier
Well-Known Member
Per Prof. Bugbee, cannabis is a race car and there is no such thing as too much light.
Markshomegrown
Well-Known Member
yeah, that's not quite true, helps to sell LEDs, if the LEDs are too close, you will flower off white buds and light can really damage your canopy.
following the advice of the video, my plants would be ok with 150,000 lux at the canopy level.
Give it a go see what happens, I keep mine around 40,000 - 60,000
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twentyeight.threefive
Well-Known Member
You obviously didn't listen to the whole video. Increased PPFD values require other inputs to be maximized as well.yeah, that's not quite true, helps to sell LEDs, if the LEDs are too close, you will flower off white buds and light can really damage your canopy.
following the advice of the video, my plants would be ok with 150,000 lux at the canopy level.
Give it a go see what happens, I keep mine around 40,000 - 60,000
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Markshomegrown
Well-Known Member
So adding some CO2 means I can give my plants over double the light?
PJ Diaz
Well-Known Member
Tell that to people growing stretchy strains that peak over 30% THC.
From seed, you should still know the genetics and whether it is an Indica or Sativa dominant variety.
It depends on what your light is to begin with, as there is always a point of diminishing returns. More CO2 will help your plants to photosynthesize better, but as @twentyeight.threefive mentioned, you also have to increase your other relational inputs. The interesting thing about CO2 is that it works even with low levels of light.
Here's a couple of good charts to consider (from - https://www.canr.msu.edu/uploads/resources/pdfs/light-co2-and-temp.pdf):
Markshomegrown
Well-Known Member
like Godfather OG or Strawberry Banana(Indica strains also have a very high level of THC)
Not always, it can be hit or miss depending on a lot of other factors, most of it comes down to the skill set of the grower to control the stretch and flower the plants off at the right time.
This chart looks about right but the video was talking about 2000, this chart only goes up to 1400?
and I can't see any point going over 900, the line is level at this point.
(TBH for anyone to use CO2, you need a sealed flower room and a way to keep the temps under control, it makes more sense to use a large flower room).
twentyeight.threefive
Well-Known Member
Do you know what the PPFD of full sunlight is? I'll give you a hint. It's in the video you called BS on.
PJ Diaz
Well-Known Member
Those are both hybrid strains, I thought you were talking about short kush type plants. I've grown strawberry banana a few times, but have better strains so let it go.
I'm not sure about that specific study or the weighting of their sensors, but here's a couple of other interesting charts, from Ball RedBook (I had to take a pic, because yes I have horticulture books).
Markshomegrown
Well-Known Member
I have bleached my canopy a few times, white buds, etc it's not fun, give it a go if you want too
Markshomegrown
Well-Known Member
This chart says it's possible, maybe with a few strains and a very high level of CO2 you could pull it off.
If my lux goes over 70k and my humidity a little low, seems to really mess my plants up, most of the best LEDs seem to be aiming for 800-1,000 par
don't see many hitting over 1,500 par(even dead center)
twentyeight.threefive
Well-Known Member
You didn't answer the question. Do you know what the PPFD of full sunlight is?
twentyeight.threefive
Well-Known Member
Markshomegrown
Well-Known Member
I don't know the PPFD of full sunlight, I don't grow weed outside but i have seen my canopy get light bleached under HPS.