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How Important Is Light Leak?

I've noticed that light leak comes up as a stress on plants with some people worrying about almost pin prick holes. Growing indoors in a tent I haven't though about it much as the light is controlled.

I planted some seedlings outside this spring and was wondering how light leak can be a problem when there is ambient light everywhere at night (moon, streetlights..) If it was a big issue it would seem to be really hard to grow anything outside.

Is the idea of light leak not that important in the end?
 

Bonsaiweed

Member of the Month: May 2018
I've noticed that light leak comes up as a stress on plants with some people worrying about almost pin prick holes. Growing indoors in a tent I haven't though about it much as the light is controlled.

I planted some seedlings outside this spring and was wondering how light leak can be a problem when there is ambient light everywhere at night (moon, streetlights..) If it was a big issue it would seem to be really hard to grow anything outside.

Is the idea of light leak not that important in the end?

Light leak can be a problem due to lights being outside the tent. If you use the space other than for growing, if you turn on lights outside the tent and it leaks in, you can have problems. Also, if a window exists in the room. If your light cycle doesn't correspond to daylight, and a window lights the room up, that can have an effect.

Those are the factors I think about when dealing with a tent......
 
As for the ambient light at night when you are growing outdoors, it's light that is constant (for the most part) and has been there the plant's whole life so that ambient won't really have an effect. where as in a grow tent, during the dark period it's usually pitch black so a pin hole (depending on if the pin hole is new or not, and depending on lighting in the surrounding room as pointed out by bonsai) can actually put a lot of stress on your plant. I'm just repeating things I've read in the past and i have no experience with this myself so if anybody sees I've given wrong information here please do correct me
 

Dwight Monk

420 Support
420 Staff
Also think it can vary a lot on the Strain/Genetics, as some you just look at them wrong and they Hermie. And others you can use the sharp learning curve and make all the normal newbie mistakes and then make some other mistakes and they still live somehow ;) :19:....I haven't had any problems with the red lights on my surge protector strips, small light leaks around doors at times, forgetting the lights are off and open the door, etc....but others have had issues with any of those things, one of those "try and control as much as you can of that" as it's never fun when it gives you problems.
 

Dwight Monk

420 Support
420 Staff
Is the idea of light leak not that important in the end?

That and you will find on many subjects there is about a 50/50 split on sides of the fence on any one issue, and can be a "whatever works for you then more power to you", and hard to say is/isn't important (or at least an etched in stone opinion ;) ) as it's a bit hard to do good scientific testing when there are so many variables and many of which are slightly different for everyone. Strain X does this and Strain Y don't care, so can be an apples and oranges kind of thing at times.......... oh you're growing in dirt/water/radioactive gel, well that's different then ;):19::19:
 
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All good points. I do try and control the light indoors with the tent but I was worried abut outside.

The idea that ambient light is a more constant source outside rather than with a tent, pitch black and then a light comes through makes sense.

After controlling factors so much indoors I'm interested in seeing how the outdoor plants do in comparison.
 
All good points. I do try and control the light indoors with the tent but I was worried abut outside.

The idea that ambient light is a more constant source outside rather than with a tent, pitch black and then a light comes through makes sense.

After controlling factors so much indoors I'm interested in seeing how the outdoor plants do in comparison.
My first grow was actually done outside, far from ideal conditions and the plants did rather well, all things considered. When i say far from ideal, i mean it was soil from the year before that had another kind of plant in it (it was a potted plant i bought from walmart, kept the pot, just pulled the dead plant out), i started late in the season, it was bag seed, forgot to water it more than i care to admit, and harvested it too early. Oh i also had 2 plants in the pot when it was probably only big enough for 1. But in the end i actually got decent quality bud, just not much of it lol. As long as you take care of it you should do fine, just make sure as it gets later into the season you keep an eye on the temp at night, and watch out for animals that might eat it on you. I'd love to see what you end up with
 

Bonsaiweed

Member of the Month: May 2018

800W-GROWER

Well-Known Member
All good points. I do try and control the light indoors with the tent but I was worried abut outside.

The idea that ambient light is a more constant source outside rather than with a tent, pitch black and then a light comes through makes sense.

After controlling factors so much indoors I'm interested in seeing how the outdoor plants do in comparison.
If you cant see 800 w in the dark from the outside, light wont get in during the day.
 

Ganjagrowergu

Well-Known Member
I have pinholes in my tent, most are taped up. We use that room for other stuff but try to limit the ceiling light being on after 7pm. I don't think it matters too much. There is other ambient light from the window, my plants are far from confused or stressed.
My wife and I decided not to worry this time around. In our case good ventilation trumped ambient light leaks. We used to black out an entire room for our tent.

Rambling now. Peace. :ganjamon:
 

800W-GROWER

Well-Known Member
I have pinholes in my tent, most are taped up. We use that room for other stuff but try to limit the ceiling light being on after 7pm. I don't think it matters too much. There is other ambient light from the window, my plants are far from confused or stressed.
My wife and I decided not to worry this time around. In our case good ventilation trumped ambient light leaks. We used to black out an entire room for our tent.

Rambling now. Peace. :ganjamon:
Once,I boarded up my front box bedroom window, with hardboard,and screwed a rug over that. I used a 1000w LAMP at the time and had the whole bedroom as a grow room. About 4 yrs I did that and nobody noticed a thing. Also,I vent out of a redundant chimney so my set up is perfect. Cops fly over head often but my heat signiture is low and is not unusual to have warm chimney`s. I now use 2x 400 HPS instead.
 

Ganjagrowergu

Well-Known Member
Once,I boarded up my front box bedroom window, with hardboard,and screwed a rug over that. I used a 1000w LAMP at the time and had the whole bedroom as a grow room. About 4 yrs I did that and nobody noticed a thing. Also,I vent out of a redundant chimney so my set up is perfect. Cops fly over head often but my heat signiture is low and is not unusual to have warm chimney`s. I now use 2x 400 HPS instead.
When I ran 1000 watt HPS I had an air conditioner in the window with doubled up construction garbage bags duct taped to the window frame. Total blackout but a/c couldn't keep up. Now I use our other bedroom and run lights during the day, window open, blinds shut with a sheet haphazardly placed over the blinds.
 

HayStack

Well-Known Member
It really depends on how big the light leak is. Pinholes are no big deal. But if your dark period is during the day and you leave your tent door open with all the windows in the room open, it might be a problem. But even if you had an exhaust fan in the roof of the tent and a small table light on. I don;t think that would make much of a difference either.
 

OttawaGreen

Well-Known Member
I told my newly growing friend light leaks are very important. Your plants need dark uninterrupted for 12 hours. He assumed despite my two decades of growing experience that I was just being overly cautious and he had a light leak - totally messed up his grow. Yield was poor and the plants had strange growth.
Try to keep them dark for all 12 hours every night period, it matters. If you can see inside the tent during lights off then it’s too bright.
 
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