Is there such a thing as to much light?

[Subtle Hustle]

Is there such a thing as to much light As long as you can keep the temp cool enough.

I could really use some good feed back on this if you guys could.

Thanks

 

[NLXSK1]

Is there such a thing as to much light As long as you can keep the temp cool enough.

I could really use some good feed back on this if you guys could.

Thanks

You would want to keep the light a certain distance from the lamps typically 200mm/250mm/300mm for 400/600/1000 watt lights.

And there is a limit to helping production somewhere beyond 50watts per sq ft...

But theoretically no, there really is not too much light, you just lose efficiency for watts not used by the plants.

 

[chronicprince]

Is there such a thing as to much light As long as you can keep the temp cool enough.

I could really use some good feed back on this if you guys could.

Thanks

There is such a thing as the lights too close.. and too much heat from a poorly setup grow.... blast light but keep it a foot away from the canopy

plan b4 you plant

 

[Subtle Hustle]

I am coming out to about 100 watts per square foot should i crank it down

 

[nitrobud]

Short answer, Yes.

Remember these plants used to grow outdoors. If you want to assume what the plants would be used to, I would look to nature. And in nature, the peak you usually see on average (well, not even average a bit higher /w canada included) is 1000 Watts a Square meter. (1 (sq meter) = 10.7639104 sq feet) so for every 10x10 area outdoors, at peak sun, there is ~1000 Watts of energy there. but this is also energy at the spectrum of the sun, not energy at the spectrum of a HPS, MH or CPF bulb.

 

[nitrobud]

I am coming out to about 100 watts per square foot should i crank it down

are your plants showing stress?

 

[T.H.Cammo]

A hundred watts per square foot may be a little high for an HID light - but it's just about right for CFL's and regular flouescents. If you are using 100watts/sq.ft. of HID light you are, pretty much, on the verge of "overkill"! It all boils down to "Bang for the Buck" and depends on your expertese at applying "The Theory of Diminishing Returns". A high tech system with beefed up ventilation and CO2 injection will support more light and more nutes.

Look at it this way. Think of the photons of light as if they were drops of rain. The ground can only absorb the water so fast, as it rains harder, the extra water just runs off - wasted (if you will). Because of the way typical plants absorb light - excess light photons can also be caused to "run off" or be wasted.

 

[T.H.Cammo]

I just reread what I wrote yesterday - it doesn't really answer your question. When you ask about "too much light", do you mean from the point of view of being wasteful or inefficient - or are you talking about actually harming the plant from some kind of light abuse?

About 50-100 watts per square foot (for HID lights) is about the maximum that most, resonable, growers use. Beyond that and the premium paid for additional electricty isn't worth the deminishing increase in yield. So yes - using "too much light" is wasteful!

On the other hand - excessive amounts of light can be harmful to cannabis plants as well. When expossed to rediculous amounts of light, the plants' pigmentation will change, first the deep green leaves will turn a paler shade, then yellowish, then a "creamy white" (if they last that long). This is the same thing that a Pathos plant will do, if left in an area that is too bright - the only difference is that it takes an awful lot of light to "bleach out" a pot plant!!! I have seen this happen with Pathos and other varieties, but with cannabis I have only read about it. The plants don't really bleach out, they just lower the amount of chlorophyll to reduce the photosynthesis as a countermeasure to all the extra photons of light. Eventually the plants will most likely croak!

 

[KaliKitsune]

There is the possibility of photosynthetic poisoning, yes, but it's very rare in cannabis plants. You're far more likely to encounter this in trees and shrubs. The sign of photosynthetic poisoning can be one of two things - either leaves lighten up *like THCammo said) or the entire plant, stems, leaves, and all, will turn an unnatural shade of purple (Look like a very diseased grand daddy purp)

Honestly, I'd not worry too much, maybe back the light off a little bit to lower the wattage per square foot. six or so centimeters should do fine enough.

 

[w99illie]

I just reread what I wrote yesterday - it doesn't really answer your question. When you ask about "too much light", do you mean from the point of view of being wasteful or inefficient - or are you talking about actually harming the plant from some kind of light abuse?

About 50-100 watts per square foot (for HID lights) is about the maximum that most, resonable, growers use. Beyond that and the premium paid for additional electricty isn't worth the deminishing increase in yield. So yes - using "too much light" is wasteful!

On the other hand - excessive amounts of light can be harmful to cannabis plants as well. When expossed to rediculous amounts of light, the plants' pigmentation will change, first the deep green leaves will turn a paler shade, then yellowish, then a "creamy white" (if they last that long). This is the same thing that a Pathos plant will do, if left in an area that is too bright - the only difference is that it takes an awful lot of light to "bleach out" a pot plant!!! I have seen this happen with Pathos and other varieties, but with cannabis I have only read about it. The plants don't really bleach out, they just lower the amount of chlorophyll to reduce the photosynthesis as a countermeasure to all the extra photons of light. Eventually the plants will most likely croak!

i just had to put in my 2 cents worth...50-100 watts per sq foot...thats a lot of light...10ft x 10ft is 100sq ft...100sq ft times 50 watts is 5000 watts...100 watts times 100sq ft is 10,000 watts...10,000 watts in a 10ft x 10ft grow is overkill in my opinion...like i said...just my 2 cents worth...its your grow room

 

[KaliKitsune]

i just had to put in my 2 cents worth...50-100 watts per sq foot...thats a lot of light...10ft x 10ft is 100sq ft...100sq ft times 50 watts is 5000 watts...100 watts times 100sq ft is 10,000 watts...10,000 watts in a 10ft x 10ft grow is overkill in my opinion...like i said...just my 2 cents worth...its your grow room

10kW in a 10x10 would be about the same brightness as full sun. that's probably the point of diminishing return.