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36 Hours of Darkness to Jump-Start Flower Cycle?


Plant of the Month: Sept 2011, Nov 2012 - Nug of the Month: Oct 2012
Hi gang,

As the subject line asks...

Does anyone know if putting a mature plant in 36 hours of darkness (Say a Broom Closet) will rapidly end the veg cycle? I've got a lot of plants outside and I am trying to find ways to bring some into flower faster without using one of my light stations, which are all currently filled to capacity. Most of these outdoor plants are far too large and heavy to carry in and out all the time, so I am looking for ideas!

What would be really great is if I could induce flowering on a few of them inside and then return them outside and have them continue to flower even though the natural light cycle here in central Cali is still 14H Day 10H Night

Really gotten into the concept of manipulating light cycle to increase yield, better control flowering onset and maintain flowering if returned to a 10 hour night cycle outside. In the past, I would just leave the plants alone outside and let them flower naturally, but at my location we are prone to early frosts, so it is always a risky proposition and I have lost some good buds to early frost before.

For those who haven't yet read my other thread about non-24 Hour flower cycles...

On Tuesday of this week I began running an iGS-15 72 hour cycle timer in my flowering room to give me a 26 hour day composed of 14 hours ON and 12 hours OFF. I'm only a couple of days into that experiment, with plants that are in Week 4 of flowering so too soon to report on any changes to growth rate, flower size etc.

Anyone out there with any first hand experience with any of this? I would love to hear what you have to say! Even if you haven't tried this yourself, feel free to chime in with questions for me or observations of other grows!

Thanks! :thumb:


New Member
Not that know the answer but isn't it like five weeks in that they,whoever they are, say the plant is too far into flower to revert fast enough to affect it?...that would be sooooooo awesome if we could just put em in dark for a day or two and just chuck em back under the light...just a thought.


Plant of the Month: Sept 2011, Nov 2012 - Nug of the Month: Oct 2012
I wasn't talking about trying to reveg the plant. I was looking for a way to speed up the plants transition from veg to flower by putting it in 36 hours of total darkness before I move it into the the Bloom Room and a 12/12 cycle. This could be a useful way to shave a few days off your next flowering session, if you still have a few days left before you harvest the plants currently in your flowering area.

Since there doesn't seem to be anyone out there that has tried this, I guess I will just have to do it myself and report back on what I find. ;)

Regarding your light cycle manipulation idea...

I would STRONGLY advise against subjecting your plants to an uneven light cycle such as what you are suggesting. Once they enter into flower, they need to stay in that mode until they are done. I only reveg the plant AFTER harvest and only if I was impressed enough with the strain to want to continue growing it out via cloning after the reveg. That is basically what I did with my Blue Cheese plant.

Those interested in revegging a previously flowered and harvested Cannabis plant should be aware that it takes about 8-9 weeks to reveg a harvested plant back to something substantial enough to take cuttings from. My BC took 8.5 weeks outdoors under primo summer sunlight conditions. I would imagine that the process would probably be even longer under artificial lighting.
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