Lighting: Why Complete Darkness During 12/12?

This is my first post. I would appreciate any good feedback. Everything I've ever read in these forums says complete darkness is required during 12/12 to simulate natural conditions during normal outdoor flowering. This doesn't seem to account for the moonlight. In my room, I have a movable 5' wall with mylar on one side for the plants on that side. On the other side, I have a window a/c. These units allow a decent bit of light in. However, the wall blocks most of it. A little bit goes over the top and makes the lamps visible. You cannot see the ground, though. Once the plants get a bit taller, they may be exposed to this minimal light (they may already be to the slightest extent). Wouldn't this be ideal rather than a problem? It's still darker on that side than it is outside when the moon is visible. I cannot avoid having darkness inside while it's light outside, so I'm hoping there is no reason this could be a problem. As far as I can tell, this condition is more natural than complete darkness, which really never occurs outside. Anybody have any similar experience that would put my mind at ease or a good reason why no light is acceptable?

I'm thinking the moon doesn't put of the same rays as sunlight for photosynthesis, so to the plants it's completely dark. That would be my guess.

the light from the moon is very faint, and lacks the intensity to degrade the hormone that causes flowering. A general rule of thumb that I'd buy is that you shouldn't be able to see your hand 6-8" from your face.

regardless of what you read moonlight can slow growth to a minimal. having light come through your closet is worst than what moonlight can do. yes the moon reflects rays of sun and gets bright. it only takes one candlewatt of light to screw it up and slow it down. so measuring in wavelengths the light that comes from the moon and the light that comes from your leaking hps or cfl light under the door is going to be considerably stronger

The light is coming from the sun. Window a/c units allow light to come in through the vents. Otherwise, the room is sealed off completely. Moonlight comes from the sun, so there should be no spectrum issues. The amount of light on one side of the wall is enough to see around well enough. On the side with the plants, it's minimal and it's above the plants. I can barely see it near the top of some of the mylar and I can't see the floor. This isn't direct light. It has reflected off of other surfaces and been weakened due to the absorption. I see your points and I appreciate them, but I still haven't heard anything definitive. I've thrown my opinion out there and I agree that this light could be stronger than moonlight. If I cover the side with the a/c with black sheets to provide maximum light absorption, I'm hoping that will reduce it to the point where I can't even see a little bit on the other side.
As far as moonlight damaging plants goes, I'm not sure that's possible. Plants were initially all grown outside and many fine ones still are.
By the way, I had to install the a/c during the last month or so of flowering during my last cycle and I didn't have any noticeable problems. I'm only on my 3rd grow and I still haven't reached the bud density that I want, but I doubt it had anything to do with the light during dark time. I know I've got too many crammed in for the light and space I have (about 40 with 2 600hps). I guess I expect mylar to work miracles. That's likely the problem with that. If anyone wants to chime in on that, I'd appreciate the input. I should just go with 25 or so I would imagine.
Has anyone had a similar issue who can give me a definite answer about minimal indirect light during the dark 12? If you know it will cause damage, what are we talking about-lower quality, density, quantity, or something else?

well the best thing to do for an indoor grow is to seal it off completely from light. use tape or whatever to fill in the gaps. if you have leaking light it will slow the flowering down. as with outdoor grows moonlight will slow it down too but hardly any at all and not enough to realize unless you had countless nights of full moons and bright nights

I have grown begonias under lights as well as more interesting things. With my begonias I found that thye flowered very poorly ifANY light got to them during the night hours. I had some on my front porch that just would not flower very well but when I moved them to the backporch, where there was no streetlight, they began to flower nicely. I was quite surprised at how sensitive they were. I keep my more interesting plants in 100% darkness after the begonia experiences.

run your lights during the day if light leaks are a problem. Or try some Black and white poly.
You will get seeds in you have light leaks.
If you can see your hand infront of your face at night then you have a problem.

I've only been in 12/12 for 3 days, but dawn comes at 3:00p.m. There's no way I could slowly or quickly move my dawn time to 6:00a.m., is there? I should've thought of this earlier. Stupid newbie.

I would move the timer in 0.5 hour increments, working backwards until you get to your desired time. Starting the first change, on the next NIGHT cycle. I would suggest you move the daylight hours, as close to your own living schedule. Good luck!!

To move your timer forward give your plants 12-1/2 hours darkness and 11-1/2 hours of light, putting the timer forward one half hour a day for when the lights go off.

gobbly said:

the light from the moon is very faint, and lacks the intensity to degrade the hormone that causes flowering. A general rule of thumb that I'd buy is that you shouldn't be able to see your hand 6-8" from your face.

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I can see about 100' or more in the dark during a full moon...

Some of this anti-light stuff is a farce. Any direct light or strong light is bad yes, but minimal light less than a moon is not. I'm not going to sweat sealing up my closet door to prevent a sliver of indirect light from getting in, it's not going to ruin the crop.

what i always wondered is, that sunlight doesnt shut off naturally trheres a mild degredation after 30-60 mins where it gets less intense... sunset... in nature it doesnt seem to go from light to black

I appreciate the advice. I hope to advance quickly enough to help others within a year or less. Sorry I tend to write so much.

Can anyone else verify that it's o.k. to move dawn time back so far as long as I do it slowly?

I obviously need the window a/c and I can't seal off the vents to block light so I've got to manage the situation in the best possible way. I've covered the lighted side with as much dark material as possible. Changing dawn is probably the only solution, assuming no one advises against it.

I know 40+ plants under 2 600w hps full spectrum is excessive. How many would u suggest? I'm currently using 2 gallon bags. I should probably go to 3+ gallons next time. As far as watering/feeding goes, I was taught to feed 6 days and flush 1. Every other day seems to be preferred. I'm switching to that now. Any advice about any of the above would be greatly appreciated. I've already accepted the fact that I'm probably going to lack density again. I just want to get everything right next time. I'd love to learn anything that can help me make the best of this one and do it right from the start next time.

I would say 10-12 anymore then that you might want to add co2. 3 gallon is best feeding and watering goes by your strain,heat amount your feeding them not days but because your just starting i would go every three unless they droop then go to every two. make sure you leave your water uncovered at least 24 hours before using. I use and recommend fox farm as nutes (and i have grown every strain that everyone of your friends rave about) also get away from mg grow soil not really for Mary its for flowers. also with two lights try the s.o.g method you will find it on this site.

I use pro mix, b mix or whatever you want to call it. Is that good? I've got diesel, white diesel, and some random good strand going at the moment. I should probably stick to 1 or 2 next time. I plan to mate them again, which is supposed to improve quality. I've read bad things about forcing hermis to get feminized seeds. How else do u do it?

I use foxfarm, by the way, for flowering along with a bit of Monte's root and bloom sometimes. I use Monte's grow formula for veg. Is that alright?

Serapis said:

I can see about 100' or more in the dark during a full moon...

Some of this anti-light stuff is a farce. Any direct light or strong light is bad yes, but minimal light less than a moon is not. I'm not going to sweat sealing up my closet door to prevent a sliver of indirect light from getting in, it's not going to ruin the crop.

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Sounds like light pollution to me... A full moon overhead in the tropics is around 1 LUX, if you can see 100' under 1 LUX then you rival or best my cat... full daylight is around 25000 LUX, with direct sunlight as high as 130000k. A rainy day (overcast) is around 1000 LUX. To give some other references, Moonless night is .002, quarter moon is .01, full moon outside the tropics is around .27. Starlight adds around .001 LUX.

Just some reference stuff: Lux is lumens divided by area. 1 foot candle = ~10.76 LUX.

I haven't seen anything scientific on it, but I have seen many outdoor grows (as well as read about thousands) and I have never once heard a grower complain that the moon was messing up their flower period. In the absence of a LUX meter, I would err on the side of caution and baffle the air intakes to cut out light.