Mythbusters

[Pipecarver]

Peer reviewed paper on sub canopy lighting @Moe.Red

https://www.researchgate.net/publication/329257744_Improving_Cannabis_Bud_Quality_and_Yield_with_Subcanopy_Lighting

Short answer? The study saw a 15% - 20% increase in yield volume overall along with an increase in terpene and cannabinoid profiles if you use red-blue or red-blue-green light spectrums.

The study also placed the lights 2 cm above soil line. As far as I understand it, the leaf tops photosynthesize while the leaf bottoms are where transpiration occurs. If this is the case then it would hold that placing lights below the leaf tops is counterintuitive to what we're trying to achieve. Placing the horizontally placed light bars 6" - 9" below the canopy line angled downward so that they are hitting the leaf tops in the undercanopy would seem like the logical place to place them for most effective photon delivery to that part of the plant. Obviously as the plants grow taller you're going to want to be able to move the SCL to best expose the plants to as much light to as many leaves as possible. SCL placement would depend on if you are growing into a screen or letting the plants grow normally. The screen grower would want to place them horizontally for the best coverage of that area whereas the normal grower would want the light installed vertically so that the entire length of the plant gets the added light energy. I would also add that it would seem that the added SCL contributes to the overall PPFD in the tent vs just the overhead light. The one thing I'm not sure of is the heat being generated from the SCL. How close can you place your plants to a 60w LED light?

It would seem that with a 15% increase in yield on a normal 2 lb tent run you're going to increase your yield an extra 5oz or more.

The SCL's I posted above total 240w between the 4 of them at a cost of $100. Estimated additional running cost for electricity would be around $10 a month. Initial light purchase of $100 + $40(4 month from veg to harvest) would mean a $140 initial outlay. Zips of weed out in Cali are going for $90. If the increase in yield is correct SCL should be a no brainer.

I've read and talked to many people about sidelighting and most don't think it does enough to warrant it but this study seems to say different.

Can anyone refute this with quantifiable data so that I don't waste $140 on broscience?

No data to offer but I was wanting side lighting for a while and I've been discouraged from it from my limited research.....I can't remember details YT video's Dr.B.B I think and a few others I watched over the years. I think its for the same reason we lollypop that just waste nutes on lower waste product or inferior buds......Not to say that we can't boost lower fruit but it may be at the expense of the top. I think there was some increase in volume but not worth the added elect cost....

I remember being keen to add more lighting and boost that lower 1/3 of the plant most chop off........but I gave up on it...

 

[moe.red]

So I read the abstract and it makes sense that side lighting helped improve lower buds.

I wonder if you scrog so there are no lower larfy buds if it helps?

 

[smoke]

Vertical lighting, i was toying with the idea of hanging a 1000 wt in the middle of my 4 plants.

 

[Rootsruler]

So I read the abstract and it makes sense that side lighting helped improve lower buds.

I wonder if you scrog so there are no lower larfy buds if it helps?

In my case, I'm tucking branches into the first week of flower then letting the remaining stretch go vertical. 9" vertical branches is what I'm shooting for as LED light doesn't really penetrate much farther into the canopy than that. The picture below shows the cola shoots that finished on stretch. Some were a little taller but no biggie.



On the GG4 scrog I did last time I pretty much kept everything tucked under the net. This time I'm allowing them to go vertical to multiply the foot print I have to work with. I filled the horizontal so now it's all about filling the vertical.

I'd like to be able to let them go taller vertically to be able to increase yields but I won't get the penetration I want to be able to reach the lower part of that. I'm hoping side lighting can do that.

 

[Rootsruler]

No data to offer but I was wanting side lighting for a while and I've been discouraged from it from my limited research.....I can't remember details YT video's Dr.B.B I think and a few others I watched over the years. I think its for the same reason we lollypop that just waste nutes on lower waste product or inferior buds......Not to say that we can't boost lower fruit but it may be at the expense of the top. I think there was some increase in volume but not worth the added elect cost....

I remember being keen to add more lighting and boost that lower 1/3 of the plant most chop off........but I gave up on it...

I'm not trying to keep from lollypopping so much as being able to grow the plant taller in the tent and be able to light the lower half. As mentioned previously, I let them go vertical up to around 9". After 9" I see flower size diminish exponentially. I'd like to grow them vertically up to 12" -14". The side lighting could power that lower 3" - 5".

The report I posted also said that it should increase cannabanoids and terpenes.

The side lights I linked are 60w each. 4 of them would equal a 240w light, so heat wise it should be equivalent to adding another COB board in the tent meaning an average rise of around 2* - 3* in the tent with lights on.

 

[Rootsruler]

Another thought I have in regards to side lighting is spectrum. What would be the effects of installing 4 separate light bars, in addition to the full spectrum SCL's, that are far red(700 - 750nm) to mimic sunrise and sunset? You could run those on a 14/10 flower schedule and reserve the first and last hour for just far red while still giving your girls their 12 hours. Once the overhead and SCL's come on the far reds turn off. On hour 13 overheads and SCL's turn off and far rights turn on for the last hour then lights off.

 

[TSD]

Some people argue that plants grown with a longer veg are more potent than the same plant flowered with a short or no veg. I'm still waiting for someone to prove it to me.

Never heard that one... doesn't make logical sense though, the genetics can do what they can do regardless of how big the plant is first right?

 

[steamroller]

I would think a plant allowed to mature without being forced would be stronger in many ways.
So I would agree without proof that longer veg is better.
Maybe just me.
I cringe when I see people flip their 2 week old plants and the like.
What is too young? I think veg should be 8 weeks minimum.

 

[TSD]

I would think a plant allowed to mature without being forced would be stronger in many ways.
So I would agree without proof that longer veg is better.
Maybe just me.
I cringe when I see people flip their 2 week old plants and the like.
What is too young? I think veg should be 8 weeks minimum.

People flip at 2 weeks? They barely have any leaves at two weeks... Well I never lol... I assumed he meant longer as in extremely long compared to a normal veg time... but I see now that he said no veg... which I guess when you flip a baby?

 

[steamroller]

Some grow 12/12 right from seed.
I am not that versed or interested in rushing mother nature.
I do like trying to help her though.

 

[Moshmen]

Never heard that one... doesn't make logical sense though, the genetics can do what they can do regardless of how big the plant is first right?

Mmmmm big and mature are two different things , this is interesting to me , I personally don’t flower young plants no alternating nodes - no flower for me ? Right or wrong?

 

[Moshmen]

I would think a plant allowed to mature without being forced would be stronger in many ways.
So I would agree without proof that longer veg is better.
Maybe just me.
I cringe when I see people flip their 2 week old plants and the like.
What is too young? I think veg should be 8 weeks minimum.

I’d most of my plants mature around then ? Hard to do a side by side on that one !

 

[TSD]

Mmmmm big and mature are two different things , this is interesting to me , I personally don’t flower young plants no alternating nodes - no flower for me ? Right or wrong?

Right, I thought that was common sense lol, thought he meant like extra long veg makes more potent plants.

 

[Rootsruler]

Some people argue that plants grown with a longer veg are more potent than the same plant flowered with a short or no veg. I'm still waiting for someone to prove it to me.

Never heard that one... doesn't make logical sense though, the genetics can do what they can do regardless of how big the plant is first right?

I can see how that might make sense. Cannabis is a perennial plant so it has it's stages just like humans. I would think that a young plants are going to have higher growth hormones running through them at this time and as they get older and conditions start to change their hormonal structure changes to accommodate the coming flowers.

 

[moe.red]

If I go for 8 weeks of veg I’ll be in trouble with height. My root ball would be massive.

 

[moe.red]

Another thought I have in regards to side lighting is spectrum. What would be the effects of installing 4 separate light bars, in addition to the full spectrum SCL's, that are far red(700 - 750nm) to mimic sunrise and sunset? You could run those on a 14/10 flower schedule and reserve the first and last hour for just far red while still giving your girls their 12 hours. Once the overhead and SCL's come on the far reds turn off. On hour 13 overheads and SCL's turn off and far rights turn on for the last hour then lights off.

I can do this with my overhead lights. Not sure what the impact under the canopy would be.

 

[moe.red]

Vertical lighting, i was toying with the idea of hanging a 1000 wt in the middle of my 4 plants.

Nightlight on the other forum did some testing with hanging HPS from pendants inside the canopy. I don’t recall the end result other than I don’t think he did it again.

 

[moe.red]

Some grow 12/12 right from seed.
I am not that versed or interested in rushing mother nature.
I do like trying to help her though.

I would never have thought to do that.

I need to think that thru a minute. Why?

 

[Moshmen]

If I go for 8 weeks of veg I’ll be in trouble with height. My root ball would be massive.

I would never have thought to do that.

I need to think that thru a minute. Why?

In ten weeks ya got weed faster than most autos

 

[Moshmen]

I keep some in solos for a month or 2 but I’m holding back not rushing em thru like you guys mmmmmm Athens convinced me I’m grabbing clones finishing out and starting automated and fresh with wool though -sorry been smokin . Lol

 

[Rootsruler]

I can do this with my overhead lights. Not sure what the impact under the canopy would be.

I'm thinking moreso for the middle and lower part of the canopy that gets shade more than anything else. What would be even better is if you could control the far reds separately from the rest of the diodes in full spectrum SCL. Then you wouldn't need the extra far red SCL. Just program the far reds to turn on first for an hour then the rest of the SCL and overheads turn on.

I'm trying to get fat flowers from net level up.

 

[ZombieRider]

The issue with TC for most growers is the sterile workspace requirements. Most folks don't have access to a laminar flow hood. Other than that, the rest is not bad.

There are some little kits out there, have not tried them. I use a rather large setup made for mushrooms.

Sup! So I made an airtight box for mycology from this tutorial (

) would that work in lieu of a laminar hood? I dont mind setting up something larger for mycology and tissue culture. I just want to make tissue cultures of my keepers so I dont have to take care of mom's all the time. Athena has made an expensive but cool tissue culture "machine" https://www.athenaag.com/culture-kit?quantity=1 " What do you think of it?

Also in response to others discussion about flipping babies, do you wait for alternating nodes to flip? Been reading up on this and the conscensus is that flipping plants before sexual maturity results in less potent/flavorful bud? I assume the pheno-hunters dont veg for long, so I wonder when the ideal time to flip is to show traits without wasting time in veg.
Anyway hope ya have a good weekend brotha! Im here smoking on some of my Double Fish breath, Velvet Moon and Banana Krumble all mixed into one joint, I call it "The week-ender" lmao.

 

[ZombieRider]

I'm thinking moreso for the middle and lower part of the canopy that gets shade more than anything else. What would be even better is if you could control the far reds separately from the rest of the diodes in full spectrum SCL. Then you wouldn't need the extra far red SCL. Just program the far reds to turn on first for an hour then the rest of the SCL and overheads turn on.

I'm trying to get fat flowers from net level up.

What are you using to give the ladies that far-red? There are a few supplemental light bars around, might pick one up and try it out. Pretty sure most led's now a days have some far reds, though at different values Im sure.

 

[moe.red]

Sup! So I made an airtight box for mycology from this tutorial (

) would that work in lieu of a laminar hood? I dont mind setting up something larger for mycology and tissue culture. I just want to make tissue cultures of my keepers so I dont have to take care of mom's all the time. Athena has made an expensive but cool tissue culture "machine" https://www.athenaag.com/culture-kit?quantity=1 " What do you think of it?

Also in response to others discussion about flipping babies, do you wait for alternating nodes to flip? Been reading up on this and the conscensus is that flipping plants before sexual maturity results in less potent/flavorful bud? I assume the pheno-hunters dont veg for long, so I wonder when the ideal time to flip is to show traits without wasting time in veg.
Anyway hope ya have a good weekend brotha! Im here smoking on some of my Double Fish breath, Velvet Moon and Banana Krumble all mixed into one joint, I call it "The week-ender" lmao.

Yes if you can do mycology you can do tc.

I flip based on where I want the plant size to be at the end. It’s not a node thing for me it’s a morphology thing. Also days is not a good metric since aeroponics and dirt grow at different rates. As do cultivars.

Your training method also plays a role in veg times. Scrogging a single plant in a 4x4 I typically veg longer.

I hope your day is as fun as I imagine it is starting.

 

[moe.red]

What are you using to give the ladies that far-red? There are a few supplemental light bars around, might pick one up and try it out. Pretty sure most led's now a days have some far reds, though at different values Im sure.

I can lend you a couple of far red sticks if you want to try. 4’ 30 watts x2.

 

[ZombieRider]

Yes if you can do mycology you can do tc.

I flip based on where I want the plant size to be at the end. It’s not a node thing for me it’s a morphology thing. Also days is not a good metric since aeroponics and dirt grow at different rates. As do cultivars.

Your training method also plays a role in veg times. Scrogging a single plant in a 4x4 I typically veg longer.

I hope your day is as fun as I imagine it is starting.

Sweetness, I will for sure be messing with TC then. More room and one can rid the plant of viruses like HLV I think as well.
And gotcha, one doesn't need to wait until the plant reaches sexual maturity to flip, just depends on how much yield you want. That being the case, one could pheno hunt pretty quickly if they just flipped after the seeds pop.

I can lend you a couple of far red sticks if you want to try. 4’ 30 watts x2.

Heck yeah, I would love to try out those far-red sticks. Im literally about to flip next couple of days, do you just run more far red at the end of flower or from the flip?

 

[moe.red]

Sweetness, I will for sure be messing with TC then. More room and one can rid the plant of viruses like HLV I think as well.
And gotcha, one doesn't need to wait until the plant reaches sexual maturity to flip, just depends on how much yield you want. That being the case, one could pheno hunt pretty quickly if they just flipped after the seeds pop.

Heck yeah, I would love to try out those far-red sticks. Im literally about to flip next couple of days, do you just run more far red at the end of flower or from the flip?

I can get these sent out on Monday, PM me

Far red has a few uses. What are you looking for? There are different purposes based on your desired result.

Also the ratio of R/FR is important. So if you start a thread with all the details like the lights you use with spectrum charts and PPFD maps if you can find one (preferably not from the vendor) I'll try to walk you thru it. Migro is a good source.

Far red can signal a shade response and make the plant grow horizontally. Helps when scrogging sometimes. But you need to start that early in veg. You can use the Emmerson Effect to increase photosynthesis. That one to me is the hardest to manage.

Also,

Each phytochrome molecule has two states called isoforms. Left in the dark for several hours, it reverts to a state called Pr, where it strongly absorbs red light (FIG. 2). If a phytochrome molecule in this state absorbs a red photon, it changes to its Pfr state, where it absorbs far-red radiation. If the molecule absorbs a far-red photon, it reverts to its Pr state. When in its Pfr state, the molecule is biologically active and may interact with the plant’s molecular machinery. Given this, a phytochrome can be seen as a reversible biological switch that can enable or inhibit various plant functions. One such important function is the detection of neighboring plants.

That Pr/Pfr stuff is hormonal, the way the plant signals sleep mode or wake mode. Using the far red for 30 minutes prior to and 30 minutes after your lights go out, you can essentially put the plant to sleep faster. This could help you to run a different schedule (longer day) which allows for higher DLI. Or you could turn the lights down a little, run an extra hour, and get the same result as 12/12 but less light intensity, which can help plants that are stressed with too many photons for their available support systems to process.

I could do on for hours on this crap, I think I'll stop here and live vicariously thru you.

 

[Pipecarver]

I can get these sent out on Monday, PM me

Far red has a few uses. What are you looking for? There are different purposes based on your desired result.

Also the ratio of R/FR is important. So if you start a thread with all the details like the lights you use with spectrum charts and PPFD maps if you can find one (preferably not from the vendor) I'll try to walk you thru it. Migro is a good source.

Far red can signal a shade response and make the plant grow horizontally. Helps when scrogging sometimes. But you need to start that early in veg. You can use the Emmerson Effect to increase photosynthesis. That one to me is the hardest to manage.

Also,

Each phytochrome molecule has two states called isoforms. Left in the dark for several hours, it reverts to a state called Pr, where it strongly absorbs red light (FIG. 2). If a phytochrome molecule in this state absorbs a red photon, it changes to its Pfr state, where it absorbs far-red radiation. If the molecule absorbs a far-red photon, it reverts to its Pr state. When in its Pfr state, the molecule is biologically active and may interact with the plant’s molecular machinery. Given this, a phytochrome can be seen as a reversible biological switch that can enable or inhibit various plant functions. One such important function is the detection of neighboring plants.

That Pr/Pfr stuff is hormonal, the way the plant signals sleep mode or wake mode. Using the far red for 30 minutes prior to and 30 minutes after your lights go out, you can essentially put the plant to sleep faster. This could help you to run a different schedule (longer day) which allows for higher DLI. Or you could turn the lights down a little, run an extra hour, and get the same result as 12/12 but less light intensity, which can help plants that are stressed with too many photons for their available support systems to process.

I could do on for hours on this crap, I think I'll stop here and live vicariously thru you.

I tried to have a mock dusk and dawn on this grow. I've 4 - 4ft red led strip lights and I strung 3 around the sides and back. I timed it for 10 min before lights out to 10 min after lights out. Same in the morning at lights on red first for 10 min then off 10 min after lights on. I did that for 1 month hoping to see an increase in bud growth......nothing........ and I was starting to wonder if it was stalling them a bit so I shut them off......

I still have them up in my 5x5 if you find a good use for them please let me know..... they're just dust catchers now

 

[Rootsruler]

What are you using to give the ladies that far-red? There are a few supplemental light bars around, might pick one up and try it out. Pretty sure most led's now a days have some far reds, though at different values Im sure.

Right now I'm relying on the lights I have that have far red in them.

I'm thinking far red as side lighting to try and mimic sunrise and sunset light color spectrum. Mounting them to the net bars or side of the tent at canopy level would also mimic the angle the light energy is hitting the leaves at. Not sure if that makes a difference but if Mama Nature does it then it must have some value.

 

[Bandit420]

I tried to have a mock dusk and dawn on this grow. I've 4 - 4ft red led strip lights and I strung 3 around the sides and back. I timed it for 10 min before lights out to 10 min after lights out. Same in the morning at lights on red first for 10 min then off 10 min after lights on. I did that for 1 month hoping to see an increase in bud growth......nothing........ and I was starting to wonder if it was stalling them a bit so I shut them off......

I still have them up in my 5x5 if you find a good use for them please let me know..... they're just dust catchers now

I have a dusk & dawn feature too. I have it set for 10 minutes. Not sure how long I can make it since I never really looked and 10 minutes seemed ideal I suppose.
I still don't know it's a good or bad thing or even needed. Maybe a slight reduction in light stress? I was also thinking maybe it helps with wear on the light? Gradually getting up to full brilliance rather than off to full power in less than a second, IDK.
Usually takes my plants an hour or so after lights on to wake up then they start to lay back down the final hour of lights on but they did that with lights I had with no sunrise/sunset feature.
I wonder if it's just a human thing where we don't like waking up to a sudden blaring alarm and prefer waking to a gradual increase in noise and light. But the more I use the dusk/dawn feature the more I think plants really don't care how they wake up indoors.