How to Use UV And IR For Growing Indoor Plants

[bluter]

UV... that high energy stuff is dangerous... we can see it clearly on our skin so why wouldn't it be the same for plants?

cannabis does avoid strong UV and can be damaged by it. it looks almost the same as a light / heat reaction. the leaves twist away so the photosynthesis side is not as exposed. that's why i'm wondering about the timing / amount to administer.

 

[Jaz]

I don't think a light can come close to putting out the uv like the sun

The sun is millions of kilometres away and your light is only metres away at most.

The lights do put out significant UV and it's recommended to switch the lights off when you go into your tent/enclosure - you will get sunburnt if you're exposed for long enough.

The UV lights in reptile tanks are piss-weak, they're designed to not output enough UV to give the reptiles sunburn. If you're going to get UV lights for your plants get the ones designed to be used for plants.


j

 

[bluter]

The lights do put out significant UV and it's recommended to switch the lights off when you go into your tent/enclosure - you will get sunburnt if you're exposed for long enough.

this is true even of leds without uv supplement and a number of hid even.

 

[Icemud]

I believe that it is the light manufacturers who are trying to convince us that these bands should be used in tandem and full time. I am not a believer and would never buy one of these lights. At least with the new Mars light, you have the ability to run both or either on a seperate timer. I plan on buying one or two of those lights.

I agree with Emilya on this...

Using Far Red (not IR) can cause plants to stretch a ton if you give them too much Far Red and not enough red, causing the plants to have "shade avoidance syndrome" Most lights that have white LED chips in them already have enough Far Red in them, and other than what Emilya mentioned in a previous post about using Far Red light for flower triggering, really there isn't much need to get extra Far Red. *unless you have very squatty indica's and purposely want to stretch them out.

UV I've seen scientific evidence going both ways with it... UV-A which is what almost all LED light manufactures use is FAR different than UV-B light on plants. UV-B chips are very very expensive and have horrible "lumen maintenance" which means they only typically last about 1/10 of the time a normal LED chip lasts because of the immense heat they give off as waste heat. UV-A is almost always what led manufactures use, which does have a lot of proof of benefit (especially in food crops as it helps produce anthocyanins, which are very good for the human body).

Plants have a receptor called the UVR-8 which actually will receive UV-A light and can benefit anthocyanin production and even drive photosytnthesis down to around 380nm.

UV-B is much harsher to the plants and therefore the active debate whether or not it helps is still to be determined. I've seen some scientific research that shows detriments to the plants for using it, although in the same test the equitorial landrace sativa seemed to be less effected by UV-B and actually increased some of the cannabinoids and terpenes.

The one thing that is heavily debated is whether UV-B and UV-A provide a "harmful" or "heathy" stress on plants. As we know, in cannabis we want to slightly stress the plants to a point where they produce more trichomes and terpenes, but the amount of stress has to be before the point of diminishing returns and this is where a lot of cannabis research is focused.

Just to add, the 1 study that is floating around that says UV is not good uses only 2 strains. As we know, science isn't just determined by a single study but by a consensus of repeatable results... And with 1000s of combinations of genotypes of cannabis and each has different reactions to the environment and how they express, I dont think a definite answer has been determined.

Honestly using a standard grow light with a 3500K-6500K color temps LEDs should have plenty of FAR RED to use and adding more isn't necessary, and some with extra UV... can it help.. maybe but the jury is still out on that.

I think most of the "hype" is from lighting companies pushing things on growers without much scientific proof backing their claims. (which has been the story of plant lighting for cannabis growers for over a decade).

And back to what Emilya said, you definitely should have control of Far RED separate from UV if adding it supplemental lighting, as the wavelengths are completely different uses and should be treated as such.

***and just a grammatical note, the light wavelengths generally referred to as IR by most lighting companies are actually "FAR RED", not IR.

 

[Oldguy1953]

If I may offer my 2 cents on this subject - for the past 2 years, I have utilized Solacure uvb tubes with varied success, This appears to be strain dependant. Prior to that I tried various reptile bulbs, and later, uvb lights for geological purposes (used for showing inflorescence of certain minerals}. The long flowering landrace sativa type can tolerate much more uvb than some of the indica types, especially those that have been worked extensively in grows indoors under artificial light (in my experience).
I have subjected the plants to various levels and times of irradiation, (checked levels with solar meter 6.2) and usually the most they will tolerate is approximately 25uw/cm2 for 2-3 hrs at their mid day. Any more than that produces damage to the leaves and as was mentioned previously, prematurely amber resin.
The uv does appear to visually increase the number of trichomes, and also the length of the trichome stalk. I also notice that the plants odor is stronger with the uvb. If the uvb is used throughout the entire grow, I have found that there is very little stretch, yet I have still gotten very good yield.
I now am using all Mars hydro equipment ( no affiliation), I have 6 sp 250, 2 sp6500, 4 solacure 4 ft fixtures, 4 Mars uv 45. I personally don't think that the FR light should be run to "wake up" the plants, but possibly a 660nm light for 5 or 10 minutes before lights on would be beneficial. I run the FR lights for 10 minutes after lights off only. This has resulted in a faster transition to flowering, and also assists in identification of m/f.
There is no disputing that good cannabis can be grown without the added wavelengths, but for myself, I prefer to emulate the sun as best I can. Also note that the uvr8 dimer is only split when uvb @ 280 -315nm is used, so selection of the light source is important.
I'm no expert, these are just things I have noticed.

 

[Icemud]

If I may offer my 2 cents on this subject - for the past 2 years, I have utilized Solacure uvb tubes with varied success, This appears to be strain dependant. Prior to that I tried various reptile bulbs, and later, uvb lights for geological purposes (used for showing inflorescence of certain minerals}. The long flowering landrace sativa type can tolerate much more uvb than some of the indica types, especially those that have been worked extensively in grows indoors under artificial light (in my experience).
I have subjected the plants to various levels and times of irradiation, (checked levels with solar meter 6.2) and usually the most they will tolerate is approximately 25uw/cm2 for 2-3 hrs at their mid day. Any more than that produces damage to the leaves and as was mentioned previously, prematurely amber resin.
The uv does appear to visually increase the number of trichomes, and also the length of the trichome stalk. I also notice that the plants odor is stronger with the uvb. If the uvb is used throughout the entire grow, I have found that there is very little stretch, yet I have still gotten very good yield.
I now am using all Mars hydro equipment ( no affiliation), I have 6 sp 250, 2 sp6500, 4 solacure 4 ft fixtures, 4 Mars uv 45. I personally don't think that the FR light should be run to "wake up" the plants, but possibly a 660nm light for 5 or 10 minutes before lights on would be beneficial. I run the FR lights for 10 minutes after lights off only. This has resulted in a faster transition to flowering, and also assists in identification of m/f.
There is no disputing that good cannabis can be grown without the added wavelengths, but for myself, I prefer to emulate the sun as best I can. Also note that the uvr8 dimer is only split when uvb @ 280 -315nm is used, so selection of the light source is important.
I'm no expert, these are just things I have noticed.

Great share! Love your real world results and experiments

You are correct about the UVR8 too... Its been probably 6 or 7 years since I researched UV light so I misspoke in my previous post.. UVR8 is UVB, not UVA like I previously mentioned good catch

Really love your info! Thanks!

 

[ChiefWhiteLegs]

I've ran the mars hydro uv ir bars as so and never had one problem. 2 weeks into flower I throw them in turn both on until harvest. Its the uvb from the t5 and t8 lighta that you have to watch. The Mars hydro uv ir 45 is safe

 

[Fenderbender]

If I may offer my 2 cents on this subject - for the past 2 years, I have utilized Solacure uvb tubes with varied success, This appears to be strain dependant. Prior to that I tried various reptile bulbs, and later, uvb lights for geological purposes (used for showing inflorescence of certain minerals}. The long flowering landrace sativa type can tolerate much more uvb than some of the indica types, especially those that have been worked extensively in grows indoors under artificial light (in my experience).
I have subjected the plants to various levels and times of irradiation, (checked levels with solar meter 6.2) and usually the most they will tolerate is approximately 25uw/cm2 for 2-3 hrs at their mid day. Any more than that produces damage to the leaves and as was mentioned previously, prematurely amber resin.
The uv does appear to visually increase the number of trichomes, and also the length of the trichome stalk. I also notice that the plants odor is stronger with the uvb. If the uvb is used throughout the entire grow, I have found that there is very little stretch, yet I have still gotten very good yield.
I now am using all Mars hydro equipment ( no affiliation), I have 6 sp 250, 2 sp6500, 4 solacure 4 ft fixtures, 4 Mars uv 45. I personally don't think that the FR light should be run to "wake up" the plants, but possibly a 660nm light for 5 or 10 minutes before lights on would be beneficial. I run the FR lights for 10 minutes after lights off only. This has resulted in a faster transition to flowering, and also assists in identification of m/f.
There is no disputing that good cannabis can be grown without the added wavelengths, but for myself, I prefer to emulate the sun as best I can. Also note that the uvr8 dimer is only split when uvb @ 280 -315nm is used, so selection of the light source is important.
I'm no expert, these are just things I have noticed.

Good to hear!
As where does the difference in flavour outdoor come from? light spectrum should be part of it... and possible communication with the surrounding environment? as plants send all kinds of triggers around and visiting insects might also trigger responses?

 

[shotnva777]

I believe that it is the light manufacturers who are trying to convince us that these bands should be used in tandem and full time. I am not a believer and would never buy one of these lights. At least with the new Mars light, you have the ability to run both or either on a seperate timer. I plan on buying one or two of those lights.

This isn't true. The new MarsHydro UV45 lights can indeed switch on seperately, but you can't put them on seperate timers, as the switches for the seperate lights are after the ballast. It sucks. It's what led me to reading this post that I found on a Google search, while searching "how to wire Mars hydro ir/uv supplement lights seperately".

I want to cut on the IR about 10 mins before my main Fluence Spydr 2p comes on. I have a cpl small seperate supplemental 660nm 12x12 panels that I'd like to run on the same timer as the IR in unison. Then, I'd like to run the UV for about 4-5 hours at my plant's "high noon". I'd also like to let the IR's run in unison after lights out as well...

So anyone know how to do this? Lol. Right now, I'm just running the IR and UV on the same timer as my Fluence, to get the complete spectrum. I figure a CMH and the sun does it, can't hurt with LEDS. Lol. My plants have loved it thus far and have ate it up, I'd like to do a side by side comparison tho

 

[Absorber]

This isn't true. The new MarsHydro UV45 lights can indeed switch on seperately, but you can't put them on seperate timers, as the switches for the seperate lights are after the ballast. It sucks. It's what led me to reading this post that I found on a Google search, while searching "how to wire Mars hydro ir/uv supplement lights seperately".

I want to cut on the IR about 10 mins before my main Fluence Spydr 2p comes on. I have a cpl small seperate supplemental 660nm 12x12 panels that I'd like to run on the same timer as the IR in unison. Then, I'd like to run the UV for about 4-5 hours at my plant's "high noon". I'd also like to let the IR's run in unison after lights out as well...

So anyone know how to do this? Lol. Right now, I'm just running the IR and UV on the same timer as my Fluence, to get the complete spectrum. I figure a CMH and the sun does it, can't hurt with LEDS. Lol. My plants have loved it thus far and have ate it up, I'd like to do a side by side comparison tho

I agree with your comment the light is pretty useless as is.
To make it switch via a timer you could use 2 relays in place of the switch on the light fitting, use double pole relays so you can use one set of contacts to power the driver and the second set to power either UV or IR.
Then do the same for the other light spectrum on the other relay .

 

[bluter]

So anyone know how to do this?

if the switch can power one or the other down, you could pull the switch and put your timers in that position to make it happen. you'd have to wire two timers in at the switch position or separate the circuits there.

if the emitters are printed together on the same bar it won't be possible as they'll be on the same circuit, you won't be able to separate the uv and ir.

 

[Absorber]

it can't be done the way those bars are printed.

both the ir and uv are powered on the same circuit. the emitters are printed on the same bar and can't be separated from each other, they are not wired individual, it's one circuit.

to do what you want you would need a separate uv and ir fixtures independent from each other.

It could be done there is a switch for UV and one for the IR so replace switches with relays

 

[bluter]

It could be done there is a switch for UV and one for the IR so replace switches with relays

check the post. i edited it to reflect the differences in circuits. if they are printed on the same bar it won't be possible though.

edit : i'm not convinced they are actually on a separate circuit. none of the specs on the light confirm it and that switch type doesn't look right.

edit : a relay doesn't do it. they need to be on separate circuits.

 

[Absorber]

check the post. i edited it to reflect the differences in circuits. if they are printed on the same bar it won't be possible though.

edit : i'm not convinced they are actually on a separate circuit. none of the specs on the light confirm it and that switch type doesn't look right.

edit : a relay doesn't do it. they need to be on separate circuits.

They can be turned on separately via the switches so a relay will do the same thing

 

[bluter]

They can be turned on separately via the switches so a relay will do the same thing

it won't separate them for independent function. i've built rigs with separate supplemental before.

it utilizes separate drivers and timers. the circuits are separated to keep the draw on the drivers from spiking when the timer trips on/off. the two systems run independently.


edit : i've added supplemental to other rigs for clients as well. i also used sell a home diy kit.

 

[Absorber]

it won't separate them for independent function. i've built rigs with separate supplemental before.

it utilizes separate drivers and timers. the circuits need are separated to keep the draw on the drivers from spiking when the timer trips on/off.

Im absolutely positive it can be done with 2 timers and 2 relays ,you aren't doing anything different that the switches do except automating it .

 

[bluter]

Im absolutely positive it can be done with 2 timers and 2 relays ,you aren't doing anything different that the switches do except automating it .

you don't need the relays with timers at all. the timers are relays. you do need separate timers.

what i don't like about this rig is the single driver. it looks like it is splitting after the driver into 2 circuits. it's not a good way to run the driver.

 

[Absorber]

you don't need the relays with timers at all. the timers are relays. you do need separate timers.

what i don't like about this rig is the single driver. it looks like it is splitting after the driver into 2 circuits. it's not a good way to run the driver.

I was thinking of using plug in timers and using a plugtop plugged into the timer to energise relays

each relay would have 2 NO contacts one to supply power to PowerPoint for driver and the other NO contact to act as the switch that way the driver isn't powered on while lights aren't on and its all still plug and play

 

[bluter]

I was thinking of using plug in timers and using a plugtop plugged into the timer to energise relays

each relay would have 2 NO contacts one to supply power to PowerPoint for driver and the other NO contact to act as the switch that way the driver isn't powered on while lights aren't on and its all still plug and play

i like that solution. it solves for the driver problem.

 

[shotnva777]

I was thinking of using plug in timers and using a plugtop plugged into the timer to energise relays

each relay would have 2 NO contacts one to supply power to PowerPoint for driver and the other NO contact to act as the switch that way the driver isn't powered on while lights aren't on and its all still plug and play

I'm not following, though I'm not too bright with relays lol. Would it be simpler to just buy a cheap driver for one or the other and just wire either the UV or IR directly to it?