What's new
  • Happy Birthday ICMag! Been 20 years since Gypsy Nirvana created the forum! We are celebrating with a 4/20 Giveaway and by launching a new Patreon tier called "420club". You can read more here.
  • Important notice: ICMag's T.O.U. has been updated. Please review it here. For your convenience, it is also available in the main forum menu, under 'Quick Links"!

Far-Red Light to reduce necessary darkness period during flowering cycle, possible ?

W

weedomat

New member
Hi

While reading in a german growing board i stumbled upon an interesting method to increase yield / reduce overall flowering time.

The theory is that one can use Far-Red light (730nm) to reduce the minimum darkness time the plant needs every day to keep flowering. Far-Red light supposedly increases the transition of Pythochrome-Pfr to Pythochrome-Pr in the plants, which triggers the creation of the hormone that keeps the plant in it's flowering cycle.

It is done by adding a far-red LED (for example: "SpectraBoost PAR-FR15") light to your normal growing light. The LED is kept running around 15mins after you normal light turns off. This is supposed to decrease the needed darkness period from 12 to 10 hours, which can be used in two ways:


  1. Increasing yield:
    By running a 14/10 light cycle instead of 12/12 one increases the amount of photosynthesis done by the plant and therefore increases yield.
  2. Decreasing overall growing time
    By using a special timer and an 12/10 cycle one can decrease day length for the plant and therefor decrease the time the plants need to mature.

My question about this is simple: Has anyone here ever tried this and knows whether this actually works ?
I've done a bit of reading and it seems that the theory behind it is sound, but somehow it all seems to good to be true :)
 
G

guest456mpy

I read a while back something about a "Martian Nights" light technique that was quite similar, but I don't have any personal experience or hard data to either prove or disprove what you have read. Perhaps someone else here has actually tried this?
 
W

weedomat

New member
I found some more stuff on this topic:

Here someone is attempting an comparison grow using 730nm and an 11/1 cycle, unfortunately it seems to fail at some point due to technical reasons
http://forum.grasscity.com/indoor-g...kis-side-side-730nm-flowering-experiment.html

Also here is another discussion about 12/10:
http://forums.cannabisculture.com/forums/ubbthreads.php?ubb=showflat&Number=1437769&fpart=2

and some more about the mechanics behind it:
http://www.uk420.com/boards/index.php?showtopic=262292
 
pezmasterelite

pezmasterelite

Member
Hi,

EDIT: Sorry if you read the old post, I re-read the initial and it was not relavant, too medicated...

I have read people using similar photo-period manipulation before with some side-effects. Are you, or the people who came up with this insinuating that the far-red light will lessen these side-effects? If so that would be interesting, I am always pondering using different spectrums of light at different times, blue in the morning, far-red at night, etc...

pez
 
gmanwho

gmanwho

Well-known member
Veteran
search
powerPAR 15-watt LED Bulb, Far Red


or 730nm led





on amazon at the time of this post a 15w screw led bulb 730nm was $46.74
 
Phaeton

Phaeton

Speed of Dark
Veteran
Initial testing was done with Phillip's 13 watt far red bulbs. No yield gains but the overall health seemed better, more and greener leaves.

For confirmation 50 watt passive bars were used for better coverage. Again, overall health was better and the sativa plants that had random seeds appearing in the lower buds lost the seeds.

After the year and a half of testing four of the fifty watt bars were put in the 5000 watt budroom surrounding the plants on all sides.

Yields never did go up. Light leaks became irrelevant, several times watering was late and fairly high light levels intruded on the dark. No matter, no hermaphrodites and no odd leaves.
The small sterile seeds that invaded buds beginning at six weeks were also gone.

But no increase in yield.

More than two hours of far red did delay bud formation, the plants kept adding leaves and growing but the buds were stalled at about the three week mark. Took almost three months to believe the buds really were not going to finish.

A very strong contradiction to the "more is better" theory.

End result: Far red is part of the spectrum necessary. Like the UVB, it does not take much but the effects cannot be denied, unspectacular as they are.
 
hyposomniac

hyposomniac

Active member
Phaeton said:
Initial testing was done with Phillip's 13 watt far red bulbs. No yield gains but the overall health seemed better, more and greener leaves.

For confirmation 50 watt passive bars were used for better coverage. Again, overall health was better and the sativa plants that had random seeds appearing in the lower buds lost the seeds.

After the year and a half of testing four of the fifty watt bars were put in the 5000 watt budroom surrounding the plants on all sides.

Yields never did go up. Light leaks became irrelevant, several times watering was late and fairly high light levels intruded on the dark. No matter, no hermaphrodites and no odd leaves.
The small sterile seeds that invaded buds beginning at six weeks were also gone.

But no increase in yield.

More than two hours of far red did delay bud formation, the plants kept adding leaves and growing but the buds were stalled at about the three week mark. Took almost three months to believe the buds really were not going to finish.

A very strong contradiction to the "more is better" theory.

End result: Far red is part of the spectrum necessary. Like the UVB, it does not take much but the effects cannot be denied, unspectacular as they are.
Click to expand...

Hi Phaeton,
Your friendly neighborhood stalker here (I just quoted you in another thread too).
What sort of timing did you use?
 
You must log in or register to reply here.

Latest posts

Latest posts

Top