To UV-B or not to UV-B?!

Growing & Learning
1

I recently picked up a Migro UVB 310 fixture and ran it for my last grow.
I used it as advised, starting at 30 min a day and slowly working up to 2 hours per during their mid-day for last few weeks.
Everything was from seed so I can’t really compare to anything but it may have made a difference to frostiness..? :thinking:

Has anyone done a solid side by side test with clones?
I’ve heard giving in short doses through the day can be better tolerated so you can give more than 2 hours per day. Anyone experimented with duration?

Plants look pretty funky under it :smiling_face_with_sunglasses:

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2

I was looking into ultra violent blue other day cause I seen something about how good it is but idk personally…those look good :+1: do u think it’s Frontier than grows without or bigger?

3

From what I’ve studied and read uv sure don’t hurt but ain’t had chance to try it personally yet. Just curious what type of main light you use?

4

Full spectrum! Or u meaning company/brand

5

Ohhh i meant led or hps? And curious about brand too

6

It’s a Mars FCE-1000w LED I dim to ~70%, and I veg with a FCE-300w at 50%. I like the bar LEDS for the perfect light spread and bought over-sized lights to run them dim and more efficient and increase the lifespan.

8

AY!
i love the effects of UVb and what they have on my plants, ive flowered out same genetics from seed (not from clone) with a UVb + IR + Full Spec light

the plants with the added UVb + IR -
where “terpier” smelling whilst growing, where more “sticky” or more “oily” for sure….. wish i could provide a perfect test but, i havnt done one sadly!

ive also only implemented UVb WITH IR. I added this side lighting after finding out about the new science done on UV and IR.

UVb is basically the safest and one of the most effective UV spectrum’s for plants, UV light being implemented will cause the plant a slight stress response, which makes the plants create a “sunscreen” like chemical to help protect against the UV!
Its shown that UVb can increase cannabinioids and terpenes in some cultivars, and i can back this, sometimes my “veg tent” turns into a flower tent because of space, and multiple times ive ran same cultivar in that tent, and my 3x3 which has the UVb+IR.

The IR effects ive noticed - i ran GHSC TrainWreck and Exodus cheese with my UV + IR recently, and it cut TrainWreck down too 7/8 flower time when it used to finish at week 9 for me!!!
The Exodus…… the terpes where so crazy, smelled like a dead rotting cheddar stuffed animal (LOL sorry but true) BUT it didnt seem too cut any time of the flowering for the Exodus (ran these cultivars many times from seed, the higher cannabinoid + terpenes is most likely mainly from the UVb)

I turn my UVb + IR + Full spec light on 30 mins before main light (stays on with main light also 30 mins), 1/2 hours mid day, and 1 hour when lights turn off (30 mins before and 30 after)

Ive noticed some wild growth using UVb + IR with autoflowers too, seems to cut up too a week off of flowering time!

Added note on IR spectrum - it dosnt trigger photosynthesis, so if using IR make sure too also use full spectrum lighting along side it, this causes it too some how utilize the IR - heres a video on YT about UV + IR effects (Check out Jug dealers YT, Dr Bruce Bugbee AND Mex Holweg!)

https://www.youtube.com/watch?v=BxV5BU5Zbyo&t=2s

https://www.youtube.com/watch?v=vWTpzZC0vv4

On another side note - Using UVb as undercanopy or side lighting will give you a lil “bump” on pest control!

9

Great for bulk and later weeks, also great for flashing seeds :call_me_hand:

10

I use a mars fc3000 4 bar 300watts

11

I watch jug dealer alot super smart and funny af but yeah great podcast :ok_hand:

12

i have used every type of light over the years. currently hlg650rspec with hlg uvb add on. uvb adds terps, and seems to reduce or eliminate disease like mildew. not an answer for bad practices buy a worthy add. hlg suggests 5% total power run with light cycle. noticed mildew elimination years ago with good cmh lights. when you are looking for that little something and you got the rest in control its worthy.

13

I think HLG only make UVA LEDs, quite different and can be run much longer than UVB CFLs.

14

yes you are right they sell uv-a add on. my mistake, now i wonder what the difference between a and b would be. i know my buds smell so strong and quality good, and no bud rot, mildew which i would get on occasion before uv-a. now i want to try adding uv-b!

15

Plants respond to UV-A a lot like intense blue light, but it doesn’t cause direct DNA damage like UV-B does, like sun tan/burn. For plants we are using to try and induce a precision stress response that I don’t think UV-A will.

16

did a little research . uv-a does nothing for potency. it does increase terpines. uv-b has no good conclusive research, sometimes improved potency sometimes not… but if uv-b is overused can reduce crop overall.i sure can grow stinkin buds these days, i’ll stick with uv-a and good lights for now.