I've been intrigued for some time by DJ Short's assertions regarding photoperiod and environment having more influence on the phenotype of a plant than most other stimuli. I was particularly taken by the premise that the 18/6 and 12/12 lighting regimes would generally tilt a 50/50 hybrid towards the indica, in terms of effects, at least. His thesis holds that the closer to an equatorial photoperiod a plant can be kept, the more likely that it will express the sativa side of its nature.
So I decided to test the theory, and try and find out a little about what's inside some of my hybrid mothers, in terms of indica/sativa balance, and whether it could be altered. I've long wondered whether a different veg period to the 18-hour standard was key to the puzzle, so I decided to try a little experiment.
I wanted to find the ideal veg period for a plant that would allow it to flower quicker, and flower more profusely. Also I wanted to find out whether changing the photoperiod would throw up any anomalies in terms of stability, etc. And of course, whether there could be a better 'standard' than 18/6 that would allow the sativa side to be enhanced - which I prefer. I'm not a couchlock kind of guy...
So - over a period of two months, I very gradually reduced my veg light period, from 18 hours to 15. I left the plants on 15/9 for one month, and observed the results. All but one plant showed signs of budding, some more than others. As expected, most of the 'indica-weighted' hybrids started budding profusely. Most of the sativa-weighted plants were more hesitant, presumably as 15 hours is not short enough to induce flowering.*
After one month, it was obvious that some plants were sliding into proper flowering mode, and so I gradually upped the photperiod again, stopping at 16 hours, where it has remained for the last three months. During that time several significant changes have happened.
The most 'indica' plant I have (by this criterion, anyway) was a Nirvana NL X BB, and this took literally months to cease flowering and begin re-vegging (by re-vegging, I mean new single-blade leaves appearing and new shoots following). Others with more sativa dominance re-vegged extremely quickly, and resumed normal veg growth.
However, the one plant I have long suspected to be NL#5, which is 25% Thai, has lost it's indica appearance, and has started growing like a Thai - much longer, fluffier buds and many more shoots with a less regular structure than before. This appears to confirm DJ Short's theory that a more sativa pheno can be 'coaxed' out of a mixed or indica-dominant pheno.
Another major discovery for me, confirmed so far on subsequent grows, is that the plants now flower far quicker than before when switched to 12/12. It used to be 10-14 days for real buds to appear - now it is 7-10. Again, all good.
The one plant that has so far resisted all photoperiod changes is my 'G13' - in quotes as I have no way of ascertaining it in reality - suffice to say it has very droopy, long-bladed leaves, and looks very indica, but it is normally somewhat sativa in growth pattern - a bit random, with weaker stems than most indicas.
My Jack Herer was binned as the final step of this experiment - it was never happy being tweaked like this, and went so out of control (in a sativa kind of way) that it was losing any sense of what it was - hard to describe, but it was as though the pheno were 'breaking apart' into 'separate personalities' (like in a horror movie!). The new, more ruthless gardener now inside me decided that this was too runty for my growroom, so I chopped it. Resistance to extreme photoperiods was another trait I wanted to check for, and it sadly failed the test...
I have no pics of any of these plants yet, but I will post some when I grow out all my mothers in a couple of months.
So - just a quick rundown of what happened to each:
Northern Lights X Big Bud (previously indica-dominant) - still pretty much indica-dominant, with great resistance to change - starts flowering at 15 hours, and has hardly stopped flowering at 16 hours (I'm still cutting min-buds off). 3 months to even begin re-vegging. However, rock-solid and very alive.
'G13' (indica leaf pattern, sativa brancing) - has hardly been affected by any of the experiment - refused to flower at 15 hours, and happily went back into veg at 16 hours. Barely no pre-flowers or pre-buds, unlike every other plant. Happy as Larry.
Crisscross (sativa-dominant, fast-flowering hybrid - the 'local C99' I like to think of it - not that I've ever tried C99!) - resisted 15 hours quite well, with very small buds appearing. Re-vegged very quickly at 16 hours, so confirming the hyrbid to be sativa-dominant.
Jack Herer (sativa-dominant pheno) - this strain just seemed to get 'confused' by the whole experiment, with many shade leaves appearing to wither as though flowering was complete, but with no flowering. Weird buds formed, but many indica-type mixed with sativa-type. Switching back to 16 hours just seemed to make it worse - by the end, it resembled DJ's desciption of the Juicy Fruit Thai, but very ill. So I binned it...sorry, Sensi...
Mystery mother (suspected to be NL#5) - this fared well, and began budding in sync with the NL X BB. The main difference was that the plant stopped flowering much more quickly when returned to 16 hours, and has adjusted it's branching and bud structure to appear much more sativa now.
The two Flos were also the first to be fully flowered from the new regime, and went from 16/8 to one week of 13/11, six weeks at 12/12 and one week at 11/13. However, as they didn't exist before it wasn't fair to include them. But they did bud in 7 days...
So the next grow will test all the non-pheno aspects of the theory - i.e. do they SMOKE more like sativas now? Of course, I will post the results in due course.
But as to the main premise that a 16/8, or other non-standard veg period may be more beneficial for 'bringing out' sativa traits in a balanced hybrid - does anyone have similar experiences or agree/disagree with the premise itself? I'd love to get some feedback.
Many thanks.
* As an aside to seed breeders, this would be VERY useful data when buying seeds - if the minimum trigger point for each strain could be published on the packet, along with the flowering period, it would make things a lot easier for issues such as this! Is that possible?
So I decided to test the theory, and try and find out a little about what's inside some of my hybrid mothers, in terms of indica/sativa balance, and whether it could be altered. I've long wondered whether a different veg period to the 18-hour standard was key to the puzzle, so I decided to try a little experiment.
I wanted to find the ideal veg period for a plant that would allow it to flower quicker, and flower more profusely. Also I wanted to find out whether changing the photoperiod would throw up any anomalies in terms of stability, etc. And of course, whether there could be a better 'standard' than 18/6 that would allow the sativa side to be enhanced - which I prefer. I'm not a couchlock kind of guy...
So - over a period of two months, I very gradually reduced my veg light period, from 18 hours to 15. I left the plants on 15/9 for one month, and observed the results. All but one plant showed signs of budding, some more than others. As expected, most of the 'indica-weighted' hybrids started budding profusely. Most of the sativa-weighted plants were more hesitant, presumably as 15 hours is not short enough to induce flowering.*
After one month, it was obvious that some plants were sliding into proper flowering mode, and so I gradually upped the photperiod again, stopping at 16 hours, where it has remained for the last three months. During that time several significant changes have happened.
The most 'indica' plant I have (by this criterion, anyway) was a Nirvana NL X BB, and this took literally months to cease flowering and begin re-vegging (by re-vegging, I mean new single-blade leaves appearing and new shoots following). Others with more sativa dominance re-vegged extremely quickly, and resumed normal veg growth.
However, the one plant I have long suspected to be NL#5, which is 25% Thai, has lost it's indica appearance, and has started growing like a Thai - much longer, fluffier buds and many more shoots with a less regular structure than before. This appears to confirm DJ Short's theory that a more sativa pheno can be 'coaxed' out of a mixed or indica-dominant pheno.
Another major discovery for me, confirmed so far on subsequent grows, is that the plants now flower far quicker than before when switched to 12/12. It used to be 10-14 days for real buds to appear - now it is 7-10. Again, all good.
The one plant that has so far resisted all photoperiod changes is my 'G13' - in quotes as I have no way of ascertaining it in reality - suffice to say it has very droopy, long-bladed leaves, and looks very indica, but it is normally somewhat sativa in growth pattern - a bit random, with weaker stems than most indicas.
My Jack Herer was binned as the final step of this experiment - it was never happy being tweaked like this, and went so out of control (in a sativa kind of way) that it was losing any sense of what it was - hard to describe, but it was as though the pheno were 'breaking apart' into 'separate personalities' (like in a horror movie!). The new, more ruthless gardener now inside me decided that this was too runty for my growroom, so I chopped it. Resistance to extreme photoperiods was another trait I wanted to check for, and it sadly failed the test...
I have no pics of any of these plants yet, but I will post some when I grow out all my mothers in a couple of months.
So - just a quick rundown of what happened to each:
Northern Lights X Big Bud (previously indica-dominant) - still pretty much indica-dominant, with great resistance to change - starts flowering at 15 hours, and has hardly stopped flowering at 16 hours (I'm still cutting min-buds off). 3 months to even begin re-vegging. However, rock-solid and very alive.
'G13' (indica leaf pattern, sativa brancing) - has hardly been affected by any of the experiment - refused to flower at 15 hours, and happily went back into veg at 16 hours. Barely no pre-flowers or pre-buds, unlike every other plant. Happy as Larry.
Crisscross (sativa-dominant, fast-flowering hybrid - the 'local C99' I like to think of it - not that I've ever tried C99!) - resisted 15 hours quite well, with very small buds appearing. Re-vegged very quickly at 16 hours, so confirming the hyrbid to be sativa-dominant.
Jack Herer (sativa-dominant pheno) - this strain just seemed to get 'confused' by the whole experiment, with many shade leaves appearing to wither as though flowering was complete, but with no flowering. Weird buds formed, but many indica-type mixed with sativa-type. Switching back to 16 hours just seemed to make it worse - by the end, it resembled DJ's desciption of the Juicy Fruit Thai, but very ill. So I binned it...sorry, Sensi...
Mystery mother (suspected to be NL#5) - this fared well, and began budding in sync with the NL X BB. The main difference was that the plant stopped flowering much more quickly when returned to 16 hours, and has adjusted it's branching and bud structure to appear much more sativa now.
The two Flos were also the first to be fully flowered from the new regime, and went from 16/8 to one week of 13/11, six weeks at 12/12 and one week at 11/13. However, as they didn't exist before it wasn't fair to include them. But they did bud in 7 days...
So the next grow will test all the non-pheno aspects of the theory - i.e. do they SMOKE more like sativas now? Of course, I will post the results in due course.
But as to the main premise that a 16/8, or other non-standard veg period may be more beneficial for 'bringing out' sativa traits in a balanced hybrid - does anyone have similar experiences or agree/disagree with the premise itself? I'd love to get some feedback.
Many thanks.
* As an aside to seed breeders, this would be VERY useful data when buying seeds - if the minimum trigger point for each strain could be published on the packet, along with the flowering period, it would make things a lot easier for issues such as this! Is that possible?
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great stuff.. hope someone can post with any expirence on this subject cause id love to know more... 
