UVB and UVA lighting - GreenPassion.org - Dedicated to Medicinal Cannabis Cultivation and Education

Hobo · #1 (**permalink**) 12-05-2007, 12:49 AM

I've heard that uvb and uva rays help increase thc production dramatically when used in supplement with your normal spectrum. as ultraviolet light doesn't exist in my HID lights, do you guys have any recommendations on a particular uva lamp?

#2 (**permalink**) 12-05-2007, 02:32 AM

mh bulbs emit uv rays..thats why i use them to flower actually it's all i use...lol...peace

Hobo · #3 (**permalink**) 12-05-2007, 10:49 AM

are you suure about that? im sure some MH will have an added UV spectrum, but not all, and certainly not the type you buy for outdoor lighting. and what are you doing for the ever important red spectrum for flowering? mh are extrememly lacking in the red spectrum, unless you have a really special bulb.

#4 (**permalink**) 12-05-2007, 12:34 PM

lol.....i love when you already have been doing something for years an someone comes along thinking they know everything....i have a enhanced red spec bulb for flower...also mh lights that are geared towards indoor growing have uv in them...do a side by side like i have with mh an hps..the hps will get you more bud that is morecompact but the mh gives out better quality...befor saying it doesn't try it..i may add a 400 hps to my 1kmh but that is as much hps as i would add...peace

midgradeindasouth · #5 (**permalink**) 12-05-2007, 12:43 PM

The blue color that a HID puts out is UVB.

The red color that a hps puts out is more of a red uv I call it uvr.

It has been proven that adding uvb to the red spec in flower will increase thc content.
This gives the plant more of a full spectrum.
Or mostly simmilar to high altitude sun light absorbtion.

This is mimicking nature as higher altitude plants seem to have a higher thc content.

Or in other words the closer they are to the sun the more thc they will have.

Some of the uvb is lost in the radiation towards lower altitudes.

midgradeindasouth · #6 (**permalink**) 12-05-2007, 12:45 PM

I would say a ratio of red:blue is 3:1 for the plants in flower at higher altitudes in the flowering season.

Where as co.'s that manufacture these lights are just now realizing this.

Hobo · #7 (**permalink**) 12-05-2007, 01:01 PM

well like i said, you prob have a special light. im not trying to sound like i know everything, im sorry if i came off that way. i wouldnt be on this forum if there wasnt a hell of a lot more for me to learn. if i had the money i would get a mogul hps with enhanced blue, rather than mh with enhanced red, you know what i mean, thats all im sayin. but im still only looking for supplimental light only uvb.

Hobo · #8 (**permalink**) 12-05-2007, 01:05 PM

my problem is, i opted for generic MH street lamp type of bulb. which doesnt contain any uv rays.

#9 (**permalink**) 12-05-2007, 01:06 PM

Quote:

if i had the money i would get a mogul hps with enhanced blue, rather than mh with enhanced red, you know what i mean, thats all im sayin. but im still only looking for supplimental light only uva.

well even the enhanced hps cant touch mh in veg...an since you get a better quality product with mh light the enhanced is great for flower...to me hps is a good light supplement but wouldn't use it alone...an im not sure if plants can use uva light...i know they use uvb...if you need a side light with uv...get lights that are geared towards reptiles..these lights are high in uv....peace

#10 (**permalink**) 12-05-2007, 01:07 PM

well even the enhanced hps cant touch mh in veg...an since you get a better quality product with mh light the enhanced is great for flower...to me hps is a good light supplement but wouldn't use it alone...an im not sure if plants can use uva light...i know they use uvb...if you need a side light with uv...get lights that are geared towards reptiles..these lights are high in uv....peace

Quote:

my problem is, i opted for generic MH street lamp type of bulb. which doesnt contain any uv rays

it was cheaper i imange...an the saying goes you get what you pay for...

Hobo · #11 (**permalink**) 12-05-2007, 01:11 PM

yea i corrected that, i meant b. im not sure i agree with you on the metal hallide. where as blue of course is better for vegging. i think hps has a stronger weak side than the mh. hps in general has an overal higher lumen output... would you agree with me on that. if that made any sense? lol

Hobo · #12 (**permalink**) 12-05-2007, 01:17 PM

actually if you look at my intro thread, you can see that i have a MH and an hps both 400w side by side. so ill see how it turns out, they are 2 weeks into flowering (ice)

#13 (**permalink**) 12-05-2007, 01:33 PM

Quote:

i have a MH and an hps both 400w

but you have a generic mh...an i do agree that hps had better lumen's thats why i said i would use it just to increase my light footprint...but i wouldn't use it over my mh or use more of it...any way like i said..you want uv extra...get some reptile lights or tanning bed lights..both contain high amounts of uv...peace

The HSIC · #14 (**permalink**) 12-05-2007, 02:08 PM

You guys both have some valid points that you've made.
Remember everyone has there own technique, that works for them.

Reptile lights will add the wanted uv rays you seek.
So far as MH vs HPS in flowering....they both do work.

Last Month I read where HPS is actually now preferred from birth thru flowering.
Month before that I read, where MH produces more potent bud in flowering, and a ever so slightly less yeild.

Which one do I believe? Both! Like I said earlier, everyone has there own technique, that works for them.

Personally, like hobo, I have two 400 watt lights, one MH and one HPS, I use em both.

Hobo · #15 (**permalink**) 12-05-2007, 02:44 PM

Quote:

Originally Posted by 2stoned

but you have a generic mh...an i do agree that hps had better lumen's thats why i said i would use it just to increase my light footprint...but i wouldn't use it over my mh or use more of it...any way like i said..you want uv extra...get some reptile lights or tanning bed lights..both contain high amounts of uv...peace

ok, to each his own. but im pretty sure that the average hps has higher overall lumens than the average mh. but this is why i use both, so i make up for weakness. i wouldn't say either of them are supplementary, rather they are both a primary combination. and i understand i get what i pay for in terms of the bulb, but im trying make a full spectrum with a couple diff sets of lights.

thank you, tanning bed lights would be nice, cause they are long florescants right? i already have a lot of florescant fixtures, or would i need a different fixture?

#16 (**permalink**) 12-05-2007, 02:51 PM

not sure about the fixtures...i do know that tanning lights get hot fast..so only use them for a couple hours a day...DO NOT RUN LIKE NORMAL LIGHTS...peace

Hobo · #17 (**permalink**) 12-05-2007, 04:04 PM

cool thanks