Do You Run UV Lights at Late Flowering?

[ViparSpectra]

UV grow lights are still expensive at the market, but recently becoming a trending to run UV lights for 1-2 hrs at the late flowering.

Do you run UV light at late flowering? How does the UV make effect to the harvest in your experience? Let's discuss more.

 

[Dub_City405]

Yes. I always run UV the last 4 weeks of flower. Start with 1 hour then I get up to about 3 hours. It denses up the buds a tad bit and it is extremely frosty ND produces more resin. But the most important is those last weeks I run the UV it keeps bugs and PM away. Or I've been lucky enough to experience no bugs or PM with UV.

 

[MIGrampaUSA]

UV grow lights are still expensive at the market, but recently becoming a trending to run UV lights for 1-2 hrs at the late flowering.

Do you run UV light at late flowering? How does the UV make effect to the harvest in your experience? Let's discuss more.

Not all UV light is equal. Are you asking if we are running UVA, UVB, or UVC? UVC is considered germicidal and would harm plant tissue. Most grow light manufacturer's are offering lights with UVA, and that doesn't do much for terpene production.

UVB is the light that triggers an increase in terpene/oil production. It also has some antimicrobial properties against pm/mold and some insects. Unfortunately, most manufacturers are not offering lights with UVB. Only a few companies are selling UVB fixtures for cannabis.

With that said, I'm running mine for 2 hrs a day during the middle of the lights on cycle.

 

[Skunk_dog]

I run UVa entire run....its 380nm Blues.... Most of these current lights rely heavy on flowering spectrum even the ones that read Full spectrum...

 

[ViparSpectra]

Yes. I always run UV the last 4 weeks of flower. Start with 1 hour then I get up to about 3 hours. It denses up the buds a tad bit and it is extremely frosty ND produces more resin. But the most important is those last weeks I run the UV it keeps bugs and PM away. Or I've been lucky enough to experience no bugs or PM with UV.

Great sharing~

 

[ViparSpectra]

Not all UV light is equal. Are you asking if we are running UVA, UVB, or UVC? UVC is considered germicidal and would harm plant tissue. Most grow light manufacturer's are offering lights with UVA, and that doesn't do much for terpene production.

UVB is the light that triggers an increase in terpene/oil production. It also has some antimicrobial properties against pm/mold and some insects. Unfortunately, most manufacturers are not offering lights with UVB. Only a few companies are selling UVB fixtures for cannabis.

With that said, I'm running mine for 2 hrs a day during the middle of the lights on cycle.

Thank you for the careful explanation. We are interested in all of these and hope to learn more about growers' habits in this area~

 

[Cirroji]

I bought a supplemental UV-B bar I plan to use in the last couple weeks of flower - however this is my first run using it.

 

[ViparSpectra]

I bought a supplemental UV-B bar I plan to use in the last couple weeks of flower - however this is my first run using it.

May you have a great result.

 

[Observationist]

I would like to experiment with UVB.

 

[MIGrampaUSA]

I would like to experiment with UVB.

Here's some ideas for UVB lighting.

MIGRO UVB 310 fixture and fluorescent tube

The MIGRO UV grow light is an 18W UV Fluorescent grow light tube and fluorescent fixture. This UV grow light delivers UVA and UVB evenly in a grow space up to 5ft x 5ft or 1.5m x 1.5m.

migrolight.com

SolarSystem® UVB

The latest generation high output UVB T5 fluorescent bulb. This system is perfect for a single light in a tent or several hundred lights in a large commercial operation.

shop.californialightworks.com

Amazon.com

I'm using both the repti-zoo light and these: https://www.growersc.com/product/uv-bars

 

[Observationist]

Here's some ideas for UVB lighting.

MIGRO UVB 310 fixture and fluorescent tube

The MIGRO UV grow light is an 18W UV Fluorescent grow light tube and fluorescent fixture. This UV grow light delivers UVA and UVB evenly in a grow space up to 5ft x 5ft or 1.5m x 1.5m.

migrolight.com

SolarSystem® UVB

The latest generation high output UVB T5 fluorescent bulb. This system is perfect for a single light in a tent or several hundred lights in a large commercial operation.

shop.californialightworks.com

Amazon.com

I'm using both the repti-zoo light and these: https://www.growersc.com/product/uv-bars

Awesome, appreciate the recs.

 

[BigBlonde]

Do you run UV light at late flowering?

No. I'm interested, though, and I am watching to see what products the leading grow light vendors develop.

 

[MIGrampaUSA]

No. I'm interested, though, and I am watching to see what products the leading grow light vendors develop.

Grower's Choice has made it pretty easy for anyone using the ROI-E720. The UV/IR bars fit right into the E720 frame and utilize a connection on the fixture. Unfortunately, it appears to be proprietary so I don't think it can be used on all light fixtures. It makes more sense to me to either pursue the Migro/California Lightworks option or purchase a UVB reptile fixture unless you're already running the E720.

 

[BBGENETIX]

UV is another one of those that can generate some discussions with folks claiming anecdotal evidence. Actual studies do not support it. Others suggest that very small amounts can be helpful and that a few seconds exposure is about all that is needed. That is also up for debate. What is certain is too much will harm yields and can harm the plants. Far red light is great.
w

 

[ViparSpectra]

UV is another one of those that can generate some discussions with folks claiming anecdotal evidence. Actual studies do not support it. Others suggest that very small amounts can be helpful and that a few seconds exposure is about all that is needed. That is also up for debate. What is certain is too much will harm yields and can harm the plants. Far red light is great.
w

Thanks for sharing your opinions.

 

[ViparSpectra]

I would like to experiment with UVB.

Would like to see your sharing about the experiment.

 

[E9noxis]

My blurple light has a secondary uvb light on it. I have to manually turn it on and off when I want to use it. It's inconvenient.

Also, I don't like the blurple light so I won't be using the uvb anymore because the regular light doesn't have a power switch. It depends entirely on the timer as a power supply

 

[ViparSpectra]

My blurple light has a secondary uvb light on it. I have to manually turn it on and off when I want to use it. It's inconvenient.

Also, I don't like the blurple light so I won't be using the uvb anymore because the regular light doesn't have a power switch. It depends entirely on the timer as a power supply

Will it affect the growth of the plant if you don't use UVB?

 

[CannabiscoJ]

A cpl tent set ups. For UV supplementation I use a few sources. Led tech still hasn't made a reliable uvb source. I primarily use flouro uv sources, 4' AgroMax UVA+, Pure Veg + UV & Pure UVB. I also have the 2' california lightworks uvb fixture and bulb. I only use UVB in the last 3 weeks of flowering aka ripening because it can affect yields if used too early or too much given. As for led uv , I have a uva & 660nm red combo bar off Amazon.. got that to fill in the 390-450nm range. I love what uv & blues do for ripening & taste plus added trichomes. Only issue is AgroMax pure UVB is powerful, it can burn your plants up in minutes if not at the right height or left on too long , CLW solar uvb light is the same.. you can smell the ozone. Patience is required because you have to slowly expose the plants to UV to stimulate the UVR8 photoreceptor & then build a tolerance to UV. It definitely works , some phenotypes respond better than others of course.
And of course either turn off the UV before entering or wear eye, face & body protection if under uv & limit your time exposure. You don't feel the damage at first , it's like welders eye.. takes time to notice. Anyways I've definitely noticed a difference since starting uv supplementation , definitely takes a bit to get dialed in but once you do the taste & terp funk increases. The biggest challenge is to give them enough but not too much, it's a fine line to gauge.

 

[LeeWD]

A cpl tent set ups. For UV supplementation I use a few sources. Led tech still hasn't made a reliable uvb source. I primarily use flouro uv sources, 4' AgroMax UVA+, Pure Veg + UV & Pure UVB. I also have the 2' california lightworks uvb fixture and bulb. I only use UVB in the last 3 weeks of flowering aka ripening because it can affect yields if used too early or too much given. As for led uv , I have a uva & 660nm red combo bar off Amazon.. got that to fill in the 390-450nm range. I love what uv & blues do for ripening & taste plus added trichomes. Only issue is AgroMax pure UVB is powerful, it can burn your plants up in minutes if not at the right height or left on too long , CLW solar uvb light is the same.. you can smell the ozone. Patience is required because you have to slowly expose the plants to UV to stimulate the UVR8 photoreceptor & then build a tolerance to UV. It definitely works , some phenotypes respond better than others of course.
And of course either turn off the UV before entering or wear eye, face & body protection if under uv & limit your time exposure. You don't feel the damage at first , it's like welders eye.. takes time to notice. Anyways I've definitely noticed a difference since starting uv supplementation , definitely takes a bit to get dialed in but once you do the taste & terp funk increases. The biggest challenge is to give them enough but not too much, it's a fine line to gauge.

What's your distance from lights to canopy? Do you think (2) agromax uv 2ft bars at 18", given in 15 min bursts, no longer than 2 hours total daily during mid 12/12, would be plant safe? Old thread, I know