when to hit em with uvb?
- Thread starter Gquebed
- Start date
rory420420
Well-Known Member
The proximity and angle of the earth to the sun during certain times of the year is more likely the source of extra spectrums,not location of the land on earth...
Notice the white blue days in spring and winter....
Jen Freddy
New Member
I use sunglasses for the purpose. These help me protect my eyes throughout the process.
Wholesale Sunglasses
Wholesale Sunglasses
bellcore
Well-Known Member
The Horti MH Blue does have a nice spectrum. Too bad the graph omits the lower UVB (280 to 315 nm). The UL rating on the Blue is only valid with the bulb in an enclosed hood but am now running w/o glass between the bulb and plant. This is my first grow with Horti.
Gquebed
Well-Known Member
So .... 47 days after the flip i flicked on the uvbs on my led panels...
If the strain is an 8-9 week finisher as said by the seed suplier Then i should be on time with the uvb, given that the buds just started chunking up this week... what should i be looking for to see if the uvb is having the desired effect? Will the trichs be longer, fatter, or just more of them?
But if this strain is 10+ wk finisher, as i suspect for 3 of the 4 girl which have very sativa dominant traits...then maybe i am a little early with the uvb? The odd thing about these sativa doms...they are starting to chunk up already too...
If the strain is an 8-9 week finisher as said by the seed suplier Then i should be on time with the uvb, given that the buds just started chunking up this week... what should i be looking for to see if the uvb is having the desired effect? Will the trichs be longer, fatter, or just more of them?
But if this strain is 10+ wk finisher, as i suspect for 3 of the 4 girl which have very sativa dominant traits...then maybe i am a little early with the uvb? The odd thing about these sativa doms...they are starting to chunk up already too...
Pepe le skunk
Well-Known Member
280-320nm is the uvb sweet spot. Not all UVB bulbs are the same quality or intensity. Zoo med and 12% Acadia bulbs(florecent) are tops.
Must be close to plants (12 inches or less for best results. Running during flowering is the only time it makes sense to use uvb when the plant is actually making thc in larger quantities. Any other time is a waste of the bulb intensity and they need to be replaced every 12-18 months before the color and intensity shift occurs in the bulb and they become paper weights. The added blue spectrum in the older uvb bulbs can have a positive effect on clones rooting and seems to promote rooting in young plants according to tests and research. (good use for your older bulbs) For higher levels mercury vapor lamps in 100 watt plus are also very good. (only downfall is they need to be moved around the sides and not just above the plants for even coverage) Remember you get what you pay for and no the cheap low watt uvb lights are a rip off and should not be used. They don't produce enough intensity or uvb in the low 280-320nm range and are garbage. UVA does nothing and make sure you wear special glasses or sun glasses when in room with them on. Ran them entire flower cycle for 12 hrs and rotated plants so exposure is to all sides every few days. Better light distribution. Hope that helps.
Must be close to plants (12 inches or less for best results. Running during flowering is the only time it makes sense to use uvb when the plant is actually making thc in larger quantities. Any other time is a waste of the bulb intensity and they need to be replaced every 12-18 months before the color and intensity shift occurs in the bulb and they become paper weights. The added blue spectrum in the older uvb bulbs can have a positive effect on clones rooting and seems to promote rooting in young plants according to tests and research. (good use for your older bulbs) For higher levels mercury vapor lamps in 100 watt plus are also very good. (only downfall is they need to be moved around the sides and not just above the plants for even coverage) Remember you get what you pay for and no the cheap low watt uvb lights are a rip off and should not be used. They don't produce enough intensity or uvb in the low 280-320nm range and are garbage. UVA does nothing and make sure you wear special glasses or sun glasses when in room with them on. Ran them entire flower cycle for 12 hrs and rotated plants so exposure is to all sides every few days. Better light distribution. Hope that helps.
RM3
Well-Known Member
Mine are on the same time as the other lights (bulbs) I run UV in veg & flower
vostok
Well-Known Member
Last week is good, but ensure you wear your sunnies before you enter the tent A+B is good together UV is used to ripen many trics early, and that is really all
any other time sis a waste, just look after your eyes so many growers fuck that up!
Dr. Who
Well-Known Member
Some well put responses here. I can tell you've done some extensive testing with UVB lighting......I have too.
The only points I might add would be that you could mention that any herp bulb will have no effect outside of 18 inch's. That's how they are designed, for out of tank safety in relation to human exposure.
The only other thing I might add would be that I got the best results from 400 watt MV's at no closer then 18" (in open wing reflectors) and for reduced times in the later stages of flower. As with your 100's you do need to move them around some but they do offer the best penetration available. You must closely monitor the trich's as it DOES accelerate maturation and can (at that intensity) quickly damage the plant if not attended to carefully. The results I got were at times impressive.....I still monkey with it for personal but, find that commercial use to be labor and cost restrictive to the end result.....
Some testing of plants by Iron labs showed a variable average increase (compared to control plants getting everything the same except the UV lighting) in overall THC between 9 - 14% strain dependent. The growing method and environmental control did play a minor but consistent variable.
That help any?
400 w MV bulbs available from
www.1000bulbs.com
Dr. Who
Well-Known Member
There are others but this one seems the best and to the point.....I have gone into more unneeded detail in one or two others here.
I think member Cobnobler may have links to at least one of those....I don't keep them...
Doc
cc2012
Well-Known Member
Cheers Doc, been reading up on this a lot and as with nearly ALL Canna related Info, Well many variations on what is best, peoples personal experience and so on..the two biggest debated points seem to Be When/for how long and amount 5% / 10%... will be doing a far bit more reading yet..I have picked up the Ballast?Controller for a Tube Light(EIKO 18/20) for the princely some of £6 off FleaBay..just in process of picking up a bulb..when see one cheap enough..
So far so good, still unsure How I'm going to run it...thinking either 10am-4pm on Timer OR from 10am-4pm but only for say 15mins in every Hour... and for the whole Grow?
Thanks again for reply
atb
So far so good, still unsure How I'm going to run it...thinking either 10am-4pm on Timer OR from 10am-4pm but only for say 15mins in every Hour... and for the whole Grow?
Thanks again for reply
atb
Yodaweed
Well-Known Member
Those Horti blue's will only give UV light if you don't have glass on your hood, the glass protects from UV light. Remove the glass and you will get more frostier buds.The Horti MH Blue does have a nice spectrum. Too bad the graph omits the lower UVB (280 to 315 nm). The UL rating on the Blue is only valid with the bulb in an enclosed hood but am now running w/o glass between the bulb and plant. This is my first grow with Horti.
Dr. Who
Well-Known Member
I would skip the veg for your first run and do it for bloom......be sure to keep either one at the earlier stated 12" and no more for sure. Run it early heavy till about "miday" then reduce on a SLOWLY sliding scale till lights out.....Increase a bit around the 4th week as the bulk starts.
After that, simply watch the trich's for finish. It will be quicker.
qwizoking
Well-Known Member
Figured i would throw this out there
uvb can increase cannabinoid production, not specifically thc. it does also rely on excess enzymes and other chems in the plant and effects arent as noticeable in all strains.
if you use it, it should be from the start of flower
uv is but a small role though in cannabinoid production . You can definitely use it in conjunction with like high pk levels and other things though to increase terpene production, both are very important for synthesis...
so inside the trichomes
Geranyl pyrophosphate and a precursor to olivetolic acid react, a c12 (for pentyl) c10(for propyl)polyketide,then through cyclization yielding olivetolic acid..then catalyzed by an enzyme to produce cannabigerolic acid along with alkylation.. The production of Thc (and propyl)thcv cbd cbdv and cbc cbcv are controlled by 3 different enzymes Thca synthase being the enzyme converting cbga to thca through an oxidative cyclization of the geranyl group on cbga(of course this is all a bit, well really simplified for y'all) geranyl diphosphate + olivetolate =cannabigerolate + diphosphate.. cannabigerolate + O(2) = Delta(9)-tetrahydrocannabinolate + H(2)O(2)
uvr8 is a photoreceptor activated by uv-b and in response will increase production of a single precursor to olivetolic acid
uvb can increase cannabinoid production, not specifically thc. it does also rely on excess enzymes and other chems in the plant and effects arent as noticeable in all strains.
if you use it, it should be from the start of flower
uv is but a small role though in cannabinoid production . You can definitely use it in conjunction with like high pk levels and other things though to increase terpene production, both are very important for synthesis...
so inside the trichomes
Geranyl pyrophosphate and a precursor to olivetolic acid react, a c12 (for pentyl) c10(for propyl)polyketide,then through cyclization yielding olivetolic acid..then catalyzed by an enzyme to produce cannabigerolic acid along with alkylation.. The production of Thc (and propyl)thcv cbd cbdv and cbc cbcv are controlled by 3 different enzymes Thca synthase being the enzyme converting cbga to thca through an oxidative cyclization of the geranyl group on cbga(of course this is all a bit, well really simplified for y'all) geranyl diphosphate + olivetolate =cannabigerolate + diphosphate.. cannabigerolate + O(2) = Delta(9)-tetrahydrocannabinolate + H(2)O(2)
uvr8 is a photoreceptor activated by uv-b and in response will increase production of a single precursor to olivetolic acid
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fishdeth
Well-Known Member
?... wut...?
