Light Leakage?

omnigr33n

I'm a damn monkey.
Joined
Sep 30, 2006
Messages
508
Reaction score
163
How much light leakage is too much light leakage? and how detrimental is a little iota of light anyway?
 
S

Stoney Bud

Guest
omnigr33n said:
How much light leakage is too much light leakage? and how detrimental is a little iota of light anyway?
Any light leakage into a flowering crop has the possiblility of creating hermies. It wastes a lot of your time and effort.
 

omnigr33n

I'm a damn monkey.
Joined
Sep 30, 2006
Messages
508
Reaction score
163
Shoot. I think Im ok for now though. My plant is like a week or two from harvest. What do u consider light leakage though? How much light is required for something to be worried about? Does it have to be constant light leakage in order to have adverse affects on the plant? Like a light leakage example?
 

schlendrake

Well-Known Member
Joined
Dec 28, 2006
Messages
323
Reaction score
4
This is just somethhing that I read somewhere.It's been said that if you need to let light into your grow area it should be no brighter than the light of a full moon. The reasoning was the light reflection in an outdoor grow at night off the moon. It went on to state that the only time an outdoor plant sees total darkness is at a new moon when there is no light reflection.

Now if you need to work in your area and need lights then you need to replace your bulbs with Green lights. Why? Cannabis for some reason are not affected by green lights. For some reason they don't process the spectrum. I've done this last year in my area and haven't had any problems with hermies or slow growth.
 
S

Stoney Bud

Guest
omnigr33n said:
Shoot. I think Im ok for now though. My plant is like a week or two from harvest. What do u consider light leakage though? How much light is required for something to be worried about? Does it have to be constant light leakage in order to have adverse affects on the plant? Like a light leakage example?
It's really not the length of time that the light is present, it's the fact that the plant has "seen" the light and it's hormone delivery within it's own system is altered by the interruption in the dark cycle.

If it's only once, here and there, for brief duration, it's a toss of the dice if it causes full or partial Hermaphrodites, or does nothing at all.

It is possible to create Hermaphrodites with only a very dim amount of light interrupting the dark cycle.

You run a risk of Hermaphrodites when using green lights as well. As I've posted elsewhere on this group before, plants see green light very well. The myth that green light isn't seen by a plant has been disproved and recognized as such by anyone in the professional botanical world. The text books used in schools will reflect this new discovery.

The poster before me has used green light of a certain spectrum and intensity and has had no ill effects. I'd hate to try that on an entire crop and turn it into a seed crop of Hermie's.

It's best to plan your day around the lights when they're on, and just stay out of the place during the light cycle.
 

Mutt

Just a Dawg
Joined
Jan 6, 2006
Messages
9,331
Reaction score
5,025
Stoney Bud said:
The poster before me has used green light of a certain spectrum and intensity and has had no ill effects. I'd hate to try that on an entire crop and turn it into a seed crop of Hermie's.
Also the "green" light bulb may be of such a low wattage that the lumens produced and the distance is such that there is not enough light to "trigger" the photosynthesis process of the plant. Also the spectrum plays a role as well. Yes the "green" is "recognized" by the plant, but a great deal IS reflected by the plant as well. There is a "threshold" of lumens required for the plant to "trigger" that hormonal response.

But as Stoney stated, its just best NOT to have ANY light during the dark period. "ounce of prevention is worth a pound of cure" IMHO
 

KADE

Aero Lord
Joined
Jul 18, 2006
Messages
1,924
Reaction score
124
Mutt said:
Also the "green" light bulb may be of such a low wattage that the lumens produced and the distance is such that there is not enough light to "trigger" the photosynthesis process of the plant.
thas what i figure, i use a green ''party'' bulb... they are only 30w max... plus the green paint on em.... doesnt give much light
 

omnigr33n

I'm a damn monkey.
Joined
Sep 30, 2006
Messages
508
Reaction score
163
Ok well let me better explain what kind of light leakage I have to deal with sometimes. I have two doors that seperate the plant. Now the main door is always shut but I leave the second door ajar a bit. Sometimes when my main living room light is on Im worried that a little light is being "seen" by the plant thru the bottom of the door in the second little closet.I mean will that little tiny amount of possibley "seen" light make a huge difference or am I being paranoid. Because Im not home all the time to make sure it doesnt go on. My family comes downstairs sometimes.
 
S

Stoney Bud

Guest
omnigr33n said:
Ok well let me better explain what kind of light leakage I have to deal with sometimes. I have two doors that seperate the plant. Now the main door is always shut but I leave the second door ajar a bit. Sometimes when my main living room light is on Im worried that a little light is being "seen" by the plant thru the bottom of the door in the second little closet.I mean will that little tiny amount of possibley "seen" light make a huge difference or am I being paranoid. Because Im not home all the time to make sure it doesnt go on. My family comes downstairs sometimes.
Yes


Just a "little" light can Hermie some strains. Whites big time.

Rule #198473628347345

Keep your plants in total darkness when appropriate.
 

ZMAN

Well-Known Member
Joined
Jan 5, 2007
Messages
186
Reaction score
1
its more or less do you feel lucky, just thro a towel down.
 
K

krotch

Guest
Stoney Bud said:
It's really not the length of time that the light is present, it's the fact that the plant has "seen" the light and it's hormone delivery within it's own system is altered by the interruption in the dark cycle.

If it's only once, here and there, for brief duration, it's a toss of the dice if it causes full or partial Hermaphrodites, or does nothing at all.

It is possible to create Hermaphrodites with only a very dim amount of light interrupting the dark cycle.

You run a risk of Hermaphrodites when using green lights as well. As I've posted elsewhere on this group before, plants see green light very well. The myth that green light isn't seen by a plant has been disproved and recognized as such by anyone in the professional botanical world. The text books used in schools will reflect this new discovery.

The poster before me has used green light of a certain spectrum and intensity and has had no ill effects. I'd hate to try that on an entire crop and turn it into a seed crop of Hermie's.

It's best to plan your day around the lights when they're on, and just stay out of the place during the light cycle.
if it has to be pitch black, then what the fudge do outside growers do about the moon?
 

ZMAN

Well-Known Member
Joined
Jan 5, 2007
Messages
186
Reaction score
1
krotch said:
if it has to be pitch black, then what the fudge do outside growers do about the moon?
The moon is does not produce enough light for the plants to use :cool:
 

schlendrake

Well-Known Member
Joined
Dec 28, 2006
Messages
323
Reaction score
4
Hey kade this is just my experiance with light. I'm sure I've had light leaks, theres no doubt. How many lumens and such I dont know but it's 200 watts of cfl light shining from one area when I open the door through the vent cover of the grow area. Now this isn't all the time maybe 4x a week for 5-10 min.

I use 2 100watt green lights to illuminate the work area(not the growing area) that is approx 12'x12'. With all of this going on I am still able to grow 24 White Widow in an area 7'x3'x8' with a 1000 watt hps as primary lighting.

In 2 years I have never had a hermie from a clone. Why is this I dont know because it goes against everything I've read. My humidity is way low/cloning style is nowhere near textbook but I have a 100% success rate. It seems as if everything that I am doing is just so contradictory to what I've seen.

So I have to believe that other things play a factor as well, such as the geenes in the plant. I'm starting to believe that theese are far more important than anything else. The reason that I say this is I have done things with my strain that should have majorly affected the sex of a clone. I have purposely tried to get a hermie to obtain pollen to breed seeds but I can't. I have had clones been near death, like all leaves were yellow and very droopy but have come back in a sog grow and produce 0 male flowers but yet produce 2oz of the stickyest bud that I have ever had. I've almost killed some with neuts to only come back and be a large producer.

So I guess that what I am trying to say before I went off like that was will light hurt a plant? I have to say that depends on the strain and the genetics of the plant as to weather it is light tolerant/temperature tolerant/stable and the such. I am by no means a pro on this plant or have even studied it but I have observed it grow and theese are just my observations and experiances.
 
S

Stoney Bud

Guest
Lets get a little more technical. When light within a certain spectrum hits the surface of the plants chlorophyll receptors, it prompts a hormone called florigen to be produced.

Another hormone named antiflorigen is produced by flowering plants. The ratio between these two hormones is what causes a plant to flower or not.

In the plants leaves, another chemical named phytochrome that is necessary to react with florigen to produce flowers.

When the phytochrome within the leaves of a plant receive a duration of light that would be considered "short day light" by that exact plant, then the antiflorigen is repressed and the florigen is increased, thus causing the plant to start flowering.

If the duration of light of correct spectrum and intensity is interrupted from a "short day", anywhere within the "dark cycle", it causes the plant to again start producing antiflorigen. The ratio between the florigen and antiflorigen is altered and flowering will decrease or stop.

This switch between ratios of florigen and antiflorigen is stressful to the plant and can cause a sexual reversal from female to male or male to female.

The result in this light hormonal stress is usually seen as Hermaphrodites. The entire plant doesn't change sex, only part of it. It will be the part of the plant that has the largest response to the florigen/antiflorigen ratio alteration.

All flowering plants use this exact system of hormones and ratios in regard to flowering.

The amount of phytochrome within the leaves of a plant determine it's reaction to light. Some plants have more, some less. The health of the plant, nutrients and humidity all are factors that determine how much phytochrome exists.

If you take all of this information and relate it to each of your plants, you'll see that in regards to light interrupting a darkness cycle, many factors come into play.

Brief interruptions of low intensity may not be sufficient to cause the florigen/antiflorigen ratio to change enough to change the plants flowering in any visible way. It can however, cause a slowing of flower growth.

The best way to not affect this ratio of florigen/antiflorigen is to leave the flowering room completely dark for the entire darkness cycle. This makes it foolproof.

Any light of sufficient strength to be "seen" by the phytochrome receptors in the leaf will have an effect on the flowering.

I hope this information provides a better understanding of the flowering sequence of plants to all of you.

Low light levels of the green spectrum may be low enough to NOT be received by the phytochrome receptors in any appreciable amount that would cause a negative alteration of the ratio between the florigen and antiflorigen.

If you have a plant that doesn't react to low level green light, then you've found a winner in the pot growing family. Of course, it may be slowing the flowering to a degree without you noticing without another test group to observe.

Here is a very good article about this subject from Botany Online:

Photoperiodism and Stimulation of Flowering

If anyone wants to read this information again, or refer to it, I've made it a "Sticky" in this area. You'll see it at the top of the menu of posts.
 

Latest posts

Top