you said this is your second grow if it`s the same setup i take it you had flashing light first time round and all was well.
as Rifleman says there could be numerous factors that lead to that end result. regards
My first grow was a Jock Horror Auto, I believe that is why I had no trouble with it. Here is what this very knowledgeable gentleman had to say on this issue.
Quote Originally Posted by ShiggityFlip
Again I would say that outdoor is far different during the night than our indoor. We must be careful discounting the effect of the far red light in late summer/fall. Studies have been done indoor with short day plants (cannabis is a short day flowering plant which actually means long night). Flowering was prevented indoor by flashing a light in the middle of the dark period each day. This is of course why gas lantern routine works well. If that same light was flashed followed by lighting from a far red bulb then flowering commenced/continued.
Its all about phytochome. Phytochrome has two light induced conformations Pr and Pfr. 660nm light will shift Pr to Pfr. 730nm (far red) will shift Pfr to Pr. If phytochrome is in the Pr state then flowering commences or continues. If it is in the Pfr state flowering will not start or ceases. Outdoor these light flashes by headlights etc, are counteracted by far red light reconverting any Pfr to Pr again. Indoor, there is no far red light in the dark cycle to do that. So if we flash a light in thee darkness it takes approximately 2 hours to convert Pfr to Pr again. If that happens just one time its not going to be a big deal. Do that quite often and there may be issues with reduced flowering response i.e buds that stretch and go half veg, hermies, reduced trichs and terps, etc.
As far as sex reversal or nanners I think that is mostly genetically determined. So if your strain is not hermie prone then having night time light issues and irregualarities will probably not make a female plant produce nanners. If it is a sensitive strain then you may have issues. Especially if there are other stressors present like excess heat, infestations, over fertilization, etc.
For me, once the lights go out I don't mess with it. Once I get these far red lights if I need to go in, I will just turn on the far reds and be confident nothing is awry.