Consequences of light leak when flowering 12/12?

chained

Well-Known Member
i grow in a small closet, and often times will leave the door about a 1/3rd of the way open in the summer to aid in cooling, and have been doing so for about, idk, 6 or so years now, and i've never had a plant hermie on me in that space, so for me, going solely off of my own personal experience, i don't buy into the whole light leaks cause hermies notion, and my grow has more light leaks than idk what, and like i said, never an issue..
to me, saying light leaks cause hermies is a good way breeders get off for putting out a so called strain that , wasn't worked worth a shit, and b, started off with one or two parents that happened to carry the hermie trait to it's offspring..
my $.02
Thanks bro, that's interesting, I assume they get no direct light... just a little ambient room light?
 

Gregor Eisenhorn

Well-Known Member
I remember when I was growing in my PC box, that I would switch the lights on in the room were it was kept with no consequences. The box wasn't light tight because of the PC fans, so I'm sure some amount of light actually got inside. But it seems that there wasn't enough to disrupt the flowering cycle. So it probably depends on the intesity of the light, if I were to point a flashlight directly at the exhaust hole, then that would probably make matters worse.

Or maybe I was lucky and got away with any additional stress.
 

ricky1lung

Well-Known Member
i grow in a small closet, and often times will leave the door about a 1/3rd of the way open in the summer to aid in cooling, and have been doing so for about, idk, 6 or so years now, and i've never had a plant hermie on me in that space, so for me, going solely off of my own personal experience, i don't buy into the whole light leaks cause hermies notion, and my grow has more light leaks than idk what, and like i said, never an issue..
to me, saying light leaks cause hermies is a good way breeders get off for putting out a so called strain that , wasn't worked worth a shit, and b, started off with one or two parents that happened to carry the hermie trait to it's offspring..
my $.02

I've left the tent wide open in the summer because of heat issues as well.
Basement lighting is cfl and they've gone full nights like that if I forgot to close up the tent. The basement lights aren't really bright, but still bright enough to illuminate the tent.
Never have I had an issue.
 

chained

Well-Known Member
Thanks for posting. I'd love for more of you to post your own stories.

I recently had some power failures, my lights came on and off multiple times over multiple days. I believe the plants have been shocked and didn't soak up the added nutrients from the res water, in effect they might have 'stalled' a bit for a day or two.

I worried at first but have asked around since. I feel okay with it now :) At this stage I don't buy this 'must have 100% darkness' idea, though I'm sure total darkness is ideal. What I have noticed is, like the OP and myself, heaps of people worry a little too much or don't really know, but when I speak to you people who have done a few grows, it's not often a problem to drop a few photons on your plants. Sure, be smart and do your best, but you might not need to pay an extra $300 on the expensive tent with no pin-holes.
 
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3N1GM4

Well-Known Member
1.) Avoid Inconsistent Flowering Light Periods & Light Leaks

  • Keep indoor lights on timer, and avoid changing the light schedule if possible

  • Prevent outdoor plants from being exposed to street lights, flood lights or other types of artificial lights during the night

  • Respect the dark period - In flowering it's important to make sure all your plants (except auto-flowering strains) get at least 12 hours of uninterrupted darkness every night. Avoid shortened dark periods and light leaks!
No matter what the strain, try to keep your plants on a consistent schedule throughout their lives, as this helps them set their circadian rhythms.

And for photoperiod plants in the flowering stage, do not interrupt the plant’s 12-hour dark period with light for any reason.

Why? During the dark period your plant is “counting” the hours until sunlight appears, and interrupting this process is one of the most common ways to stress the plant to produce bananas or hermies. It can also cause your plant to revert back to the vegetative stage.

Along with the point above, make sure you do not have any light leaks in your grow space, which could allow outside light to filter in during the dark period. During the dark period your plants like complete darkness.

If anything ever happens with your timer or power that causes your plant to get too much light or darkness, it’s important to correct your timer as soon as possible. But don’t worry about it too much if it happens just for one day. It's usually okay if it happens only once, but be careful not to let it happen again since too much messing up the light schedule can cause hermies.

Fem seeds are more prone to herm because it is in their genetics.
http://www.growweedeasy.com/male-plants-bananas-hermies
On another note, plants can also be resistant to herm by strong bred genetics
 

smegpot

Well-Known Member
The consequences are stretchy plants that take double the time to to finish best case scenario. Weed needs 100% dark for 12 straight hours. You can do 24 hours of light on and 12 hour dark periods if you want to try it. I have experimented with that schedule and it does work but its not really energy efficient...and not really easy to do (nor really any gains). You have to have a really encapsulated system like a tent or closet to try it.

I still don't understand how people get hermies regularly. It either shows pistols or its gone. Maybe I am too black and white concerning this and that's why I've never had any in flower (possibly chopping perfectly good females?). To me its either show pistols or gone. No wishy washy could be balls, could be pistols. Anything other than a set of pistol at 5-6 weeks veg goes into the trash bin. I've never had bananas either.
 

az2000

Well-Known Member
I'm convinced it's the variations in light exposure that may cause herms.
I'll bet that a light leak occurring at the same time everyday wouldn't have an effect....street lights, moons, growers leaving their closet door open, etc.
That's an interesting theory. It makes sense. It's not the light but the abruptness. If it comes on gradual (and leaves gradually) like the moon. Or, is always present like a streetlight (but not enough to keep it out of flower), then it's just a different kind of "darkness" -- not a stress.

Best explanation yet.
 

Gregor Eisenhorn

Well-Known Member
I'm convinced it's the variations in light exposure that may cause herms.
I'll bet that a light leak occurring at the same time everyday wouldn't have an effect....street lights, moons, growers leaving their closet door open, etc.
Something like the Gas Lantern Routine? The extra hour of light everyday at the same time is the case, that's why there are no hermies then.
 

bird mcbride

Well-Known Member
It's all in the seed. Nothing to do with stress. The only reasons we use propane lanterns is for co2 and power failures.
I have grown countless seeds and if it's female it stays female...for years.
 

dmckay72

New Member
I have four White Widow plants on day 55 of flower but they just have the pistils coming in and have not formed any buds. This is the fourth grow and all the others went great with the exception of a few hiccups over or under feeding. The only thing I can think that may have happened is light leaking through a few pinholes in the tent from a hallway light. It would be miniscule, but I can't find any other reason. I have sealed any small leaks and will see what happens. I suspect they reverted to veg as they have stretched more in the last few weeks. Bummed!
 

Thundercat

Well-Known Member
I have four White Widow plants on day 55 of flower but they just have the pistils coming in and have not formed any buds. This is the fourth grow and all the others went great with the exception of a few hiccups over or under feeding. The only thing I can think that may have happened is light leaking through a few pinholes in the tent from a hallway light. It would be miniscule, but I can't find any other reason. I have sealed any small leaks and will see what happens. I suspect they reverted to veg as they have stretched more in the last few weeks. Bummed!
Pinholes will not stop them from flowering. How long did they be for before you flipped? Plants don't begin flowering instantly when you flip to 12/12. They must go through a transition period from veg to flower. That typically takes 7-21 days, but I highly dependent on the genetic maturity of the plant your growing and tour environment. Flower does NOT begin until the plant begins to form flowers!

I recently had clones that normally take 7-9 days to begin flowering that took over 20 because of some extreme cold this winter. They are flowering great now!
 

HitemwiththeHine

Well-Known Member
One thing I like to do is use green led bulbs in any light fixtures in the room. I have a regular white color bulb over my work table.

That way, if I need to work in the room I can still flip the lights on. I use tents, so the plants are in the dark anyway, but this way if I'm in there and there's a leak I'm not aware of, at the very least it's minimized by the green light (I think. I hope.).
SmartSelect_20190319-211814_Chrome.jpg
I use these in my passive intakes. I take a piece of black a/c filter sheet cut round to size, wedge it into the above vent, and zip tie the tents vent sleeves around the outside. The black filter sheet is dark enough to block light but lets plenty of air through. Keep the passive vents closed.

I haven't always done it this way. Personally I think I've only ever seen stress seeds if I was stressing it some other way (heat, rough LST), but I can't exactly ask.
 

AT098

New Member
Anyone had it happen first hand? Just how much light were the plants exposed to, and for what duration?
I know this is old but I just had it happen. Light leakage is very real and happens easily. It has cause my one and o Ly blueberry Kush plant to produce some seeds. Not bananas\ pollin sacks. I'm going to keep the very few I see I believe the seeds in this situation are feminized( forcing a flowering female into male, in this case accidently by light leakage. But I don't want to remove the seeds and stress it or make it grow more to replace them. I'm going ride out the storm lol and harvest on schedule or maybe if it gets out of hand a bit early. I'm no expert so I might be incorrect with the fem seeds thing but I do have experience
 

Gingeroot

Well-Known Member
I think it’s 90% genetics. Idk how many times I’ve left a tent or closet open, went months without noticing a timer light being on, or had a pet peel back curtains or open doors...I usually blame genetics or if it happens often at abrupt times.
 
Anyone had it happen first hand? Just how much light were the plants exposed to, and for what duration?
Yes. I added a smaller led spot-light just to fill in what I perceived to be an area of low light, and set it for the same 12/12 as everything else. At some point, that timer failed, and that single led light remained on 24/7 for what I suspect was a week. (It was a small led, about 20W.) My initial observation is that the half of the plants that were closest to that problem light are growing new bud MUCH slower than the other half. They could be reverting to veg, but I'd be surprised if it's irreversible.

So... I came here to see what to expect...

I certainly don't see any hermaphrodites, but I'll watch.
 
...further to my post above, in case anyone is assessing damage from light vs. distance, the affected plants were all within 3ft. of a 20 watt led. It's a far cry from an underdriven half-watt indicator led.
 
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