Do You Run UV Lights at Late Flowering?

[GrowMonster]

This is my first run experimenting with uv. I got mine 17" away from tops. The uva led bars are 24 watt. Got 2 in there and run them 10min every hour during lights on. I got sun blaster blast and reflector to go with the agromax uva+uvb bulb (also 24watts). I run it from 1hr 3x a day during lights on. I give them a 3 hr rest between blast. The mature auto plants are in bloom and i can't see a difference as of yet. But I'm hoping terps and trichs are top shelf. I've never grown these strains before so I have nothing to compare it to. I had seedlings and early veg in tent also. The plant in veg started turning purple under those lights and loved it. When I moved her to the veg tent she stopped the color change and doesn't look as vigorous. Might need to get this sit up for another tent. I purchased it also for the benefits of pest and mold control but I heard u need to use it differently for that benefit. Last 2 weeks of bloom i will blast them for 6 hrs strait. They say that's how u get those extra benefits. I'm at start of week 5. I'll give yall more info from my view in about a month. Yeah my main light is 240 watt viparspectra on full blast. This was a test run first for me with alot of things which is why my autos are so small. Went from seedling to bloom with no veg time.

 

[amneziaHaze]

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.

there is a reaserch if uvc is used for 2 seconds each day it reduces powdery mildow by 40% and harms the plant as much as uvb

 

[krustysurfer]

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.

Inexpensive reptile bulbs supply the UVA, UVB, and far infrared.
Careful though , they get hot, probably only run them for 45 minutes.

 

[CannabiscoJ]

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

Yes just watch the distance depending on the percentage of uvb.. if it's uvb you don't want it too close to burn the leaves. Start slowly and gradually work on distance and duration. Good luck and sorry I took so long to reply.

 

[Glassdub]

I just ordered a MIGRO UVB 310 for my 5'x5' tent with HLG Scorpion Rspec as my main light & I'm curious what would be the best placement for hanging I could cross the non lit parts for the Rspec but would think it would be far too close since the suggestion is 2' from the canopy & I'm currently at 15", into the 3rd week of flowering.

 

[CannabiscoJ]

I just ordered a MIGRO UVB 310 for my 5'x5' tent with HLG Scorpion Rspec as my main light & I'm curious what would be the best placement for hanging I could cross the non lit parts for the Rspec but would think it would be far too close since the suggestion is 2' from the canopy & I'm currently at 15", into the 3rd week of flowering.

I'm not to sure about the migro because it's 310nm and a T8 , I use AgroMax it's 285nm & H.O. T5 I know I need at least 2-3' from canopy or it can fry them. I only use uvb in ripening phase of flower, running uvb all flower can hurt yields, but again it's 310nm instead of 285 nm and less intense. The other type I use is cLW theirs is 285 nm as well and I need 2-3' from canopy. I've read others that install a dimmer supposedly that helps. Sorry I'm not quite familiar with the migro 310 , I have the aray model for the uniformity but have no experience with his uvb light. I'd say for safety reason to start further away and gradually move closer to avoid uv burn. I do use uva from seed to harvest, but uvb only after bulking is done in flower 6wks give or take, right before ripening phase. I've tried running it full flower and it can cause stress and nanners , so I picked up a AgroMax pureveg + uvb. Its alot less intensive as the 75% uvb pureUV & CLW uvb light. I only run them for a cpl minutes in the middle of lights on to replicate high noon uvb like outside. Just becareful, uvb is no joke. I know there are other people on here with the migro 310 so hopefully they can chime in and give us specifics. Duration & distance. Light placement is hard when supplementing.. I just try to do my best.

 

[Glassdub]

FYI: From Migro
"The UVB fixture will need to hang above the Rspec light, the entire plant does not need to receive direct UV light so you should be fine with this arrangement."

 

[C0pperh3ad]

Solacure

 

[Glassdub]

Preview hang

 

[madweed420]

This is my first run experimenting with uv. I got mine 17" away from tops. The uva led bars are 24 watt. Got 2 in there and run them 10min every hour during lights on. I got sun blaster blast and reflector to go with the agromax uva+uvb bulb (also 24watts). I run it from 1hr 3x a day during lights on. I give them a 3 hr rest between blast. The mature auto plants are in bloom and i can't see a difference as of yet. But I'm hoping terps and trichs are top shelf. I've never grown these strains before so I have nothing to compare it to. I had seedlings and early veg in tent also. The plant in veg started turning purple under those lights and loved it. When I moved her to the veg tent she stopped the color change and doesn't look as vigorous. Might need to get this sit up for another tent. I purchased it also for the benefits of pest and mold control but I heard u need to use it differently for that benefit. Last 2 weeks of bloom i will blast them for 6 hrs strait. They say that's how u get those extra benefits. I'm at start of week 5. I'll give yall more info from my view in about a month. Yeah my main light is 240 watt viparspectra on full blast. This was a test run first for me with alot of things which is why my autos are so small. Went from seedling to bloom with no veg time.

If you grow, you have to try uvb, it's a must, big difference, I run mine 12 hours day till end of flower starting from 2 weeks after germination, you need to know how to use uvb lights because at certain distance the uvb light UVI index will be 3 to 7, know the distance of your uvb light and at that distance where on the UVI index it is, then look up the time to burn for that UVI index, for example UV index of 6 takes 30 minutes to burn, don't expose your plants more than 30 minutes a day to the uvb light, I divide the 30 minutes by 12 hours a day which gives me 2.5 minutes of exposure an hour, rather than leaving the light on for 2.5 minutes I further split 2.5 minutes throughout the hour, I run mine with an on time of 21 seconds every 5 minutes at an UV index of 6 during veg for 12 hours and decrease it from 12 hours to 6 hours and increase the on time to 42 seconds every 5 minutes during flowering for 6 hours simulating the 10 pm to 4 am peak UV index radiation during summer