ikinokori
Active member
thank you. Your english is very fine and i perfectly understood you, don't worry mine is not great either. I have been able to download the study and it is a very interesting study which shed some light, as i do not know exactly the effect of uvb on cannabis. i just added it because i tried to mimick the sun as closely as possible. I thought that it could potentially increase thc, but i did not know it could effect other cannabinoids too, so that is very interesting.
Regarding the introduction of uvb, i think you are totally right about being wary of uvb, it is indeed a big stress to them i found. However, i think i have found that it is possible the need for very progressive exposure may be valid mostly in that scenario where you introduce uvb late i think. During my trials, what i found is that starting uvb exposure as soon as possible reduces a lot the impact on them. Introducing during middle of flo did do what you described and my old blueberry suffered for a while. I guess it is probably because they developped their whole life without any uvb in sight, so no defense against it. In that case, progressive exposure is what needs to be done, pribably since they have no defense against it since they never saw any uvb, like ever. But outside the world of indoor growing, when you think of it, the sun of those landraces countries output much more uvb than any lamp can output and there is no progressive output, they get it from the start. that is why during this grow, i introduced it as soon as possible and to my surprise, it did not seem to affect at all the plants in their overall developpment when it did for my previous grow. the current plants grew even more vigorously than those who were in veg without a single uvb, showing that at least they could still manage it fine, the honduras being the fastest, most resiliant and most vigorous plant i have ever had, while also being the strain that was the most exposed to uvb.
I have been in south america, and the uv is so strong there you can't even go out sometimes. I have the value of how much uv my lamp exposes to my plants at a certain distance, and even very close, it would only slightly match the one from brazil. So maybe, i believe it is possible the key is that it is very important to expose to it as soon as possible, because as you say, it is a stress, and i think they may need to learn to deal with it since the beginning and, i don't know, maybe do something like develop a resistance to it, like us human do (a german that never left germany will probably burn instantly in jamaica, but if he were born there, his skin would be much more adapted to it for example).
i was scared it may kill them, but to my surprise it did not do any ill effect, stopped the insane initial stretch of the honduras that made them so skinny and not stable and i even think it started making it focus on growing more leaves. I do not know why, but since they are landrace, maybe that is why they don't like indoors, because if i take back the litterature i found a while back, the plant outside will keep stretching to reach more blue/uv and then will reduce the stretch. And what i understand about landrace and non landrace, is that they lose the title "landrace" when the strain has been either hybridized or adapted to grow "indoors". So maybe what is needed for a landrace to grow properly indoors, is to have been grown indoors with traditional grow lamps (none of them emit real uvb as uvb is concidered a health hazard, at least where i live and the only way to get it is with reptile lamps) and got them used to not have any uv light for several generations maybe ? It is just a theory of mine, so maybe it is not the case but i always wondered what was "lacking" indoors vs outdoors and it looks maybe like a potential candidate for that i think, even though there may be more than just that.
for the shadow light, i thought the plants mostly reflected green and tat is actually why they were green ? Either way, i have no idea what the shadowed light spectrum looks like as i never saw anything showing that so that may be possible. The only thing i saw in the study was that in the shadow, the plant receive a lot less blue, and specifically almost no uv at all, while still receiving a lot of red and infrared, and that being above in the sun makes the plant receive suddenly a lot of blue and uv. they did not say it was about proportion, but it may have been what is implied, that the importance was the ratio of blue/uvb to red/infrared. I don't think being shadowed can "increase" the amount of red and infrared received, just make it much more dominant compared to blue uv, so it may have been what the study was saying. This would be a cool thing to experiment with mother and clones, maybe i will do it in the future
Regarding the introduction of uvb, i think you are totally right about being wary of uvb, it is indeed a big stress to them i found. However, i think i have found that it is possible the need for very progressive exposure may be valid mostly in that scenario where you introduce uvb late i think. During my trials, what i found is that starting uvb exposure as soon as possible reduces a lot the impact on them. Introducing during middle of flo did do what you described and my old blueberry suffered for a while. I guess it is probably because they developped their whole life without any uvb in sight, so no defense against it. In that case, progressive exposure is what needs to be done, pribably since they have no defense against it since they never saw any uvb, like ever. But outside the world of indoor growing, when you think of it, the sun of those landraces countries output much more uvb than any lamp can output and there is no progressive output, they get it from the start. that is why during this grow, i introduced it as soon as possible and to my surprise, it did not seem to affect at all the plants in their overall developpment when it did for my previous grow. the current plants grew even more vigorously than those who were in veg without a single uvb, showing that at least they could still manage it fine, the honduras being the fastest, most resiliant and most vigorous plant i have ever had, while also being the strain that was the most exposed to uvb.
I have been in south america, and the uv is so strong there you can't even go out sometimes. I have the value of how much uv my lamp exposes to my plants at a certain distance, and even very close, it would only slightly match the one from brazil. So maybe, i believe it is possible the key is that it is very important to expose to it as soon as possible, because as you say, it is a stress, and i think they may need to learn to deal with it since the beginning and, i don't know, maybe do something like develop a resistance to it, like us human do (a german that never left germany will probably burn instantly in jamaica, but if he were born there, his skin would be much more adapted to it for example).
i was scared it may kill them, but to my surprise it did not do any ill effect, stopped the insane initial stretch of the honduras that made them so skinny and not stable and i even think it started making it focus on growing more leaves. I do not know why, but since they are landrace, maybe that is why they don't like indoors, because if i take back the litterature i found a while back, the plant outside will keep stretching to reach more blue/uv and then will reduce the stretch. And what i understand about landrace and non landrace, is that they lose the title "landrace" when the strain has been either hybridized or adapted to grow "indoors". So maybe what is needed for a landrace to grow properly indoors, is to have been grown indoors with traditional grow lamps (none of them emit real uvb as uvb is concidered a health hazard, at least where i live and the only way to get it is with reptile lamps) and got them used to not have any uv light for several generations maybe ? It is just a theory of mine, so maybe it is not the case but i always wondered what was "lacking" indoors vs outdoors and it looks maybe like a potential candidate for that i think, even though there may be more than just that.
for the shadow light, i thought the plants mostly reflected green and tat is actually why they were green ? Either way, i have no idea what the shadowed light spectrum looks like as i never saw anything showing that so that may be possible. The only thing i saw in the study was that in the shadow, the plant receive a lot less blue, and specifically almost no uv at all, while still receiving a lot of red and infrared, and that being above in the sun makes the plant receive suddenly a lot of blue and uv. they did not say it was about proportion, but it may have been what is implied, that the importance was the ratio of blue/uvb to red/infrared. I don't think being shadowed can "increase" the amount of red and infrared received, just make it much more dominant compared to blue uv, so it may have been what the study was saying. This would be a cool thing to experiment with mother and clones, maybe i will do it in the future
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