After some research, I am going to add uvb lights.
question. Where to get a good light at.
2nd, when do I add it to the grow?
thank you
I prefer UVA 285-315 nm over UVB. UVB is for reptiles and causes sun burrn, an can cause skin cancer for humans. UVC is used for bacteria controls.
Most folks using UVB get a 2' reptile t5 style light and use it on a limited basis. Most reptile houses have them for sale $20-40 per tube.
Aha .....now we are getting some where. Thank you me.
I did not know that only a couple of hours.
Have you ever tried these reptile lights?
Forget the Reptile lights.

Arcadia Dragon Bulb 54w T5 is the best made, and its nowhere near as powerful as a Solacure Flower Power 34w bulb. These are also overbuilt, and can be run as high as 80w, but theres no reason for that.

They also make 100w. No reason for them for this purpose.


FR40T12 multi-wattage, multi-peak UVB/UVA horticultural lamp.
Wattage: 32-40 watts standard, can be run as high as 80w for special applications.
Color: white to violet. Color temperature >10,000K
Dimension: 4 foot by 1.5 inches. Will fit almost any shop light.
Reflector: Built inside the lamp. No external reflector needed.
UVA/B: 5x the power of the SG-1 and Universal UV. About 20 to 50x the power of reptile lights.
UVA/B rating: Equivalent to a 30% UVB lamp, but we do this in very different frequencies, so they don't equate.
Life: 1000 hours at 70% of original power.

From the ground up, this lamp was engineered to do nothing but operate as a horticultural lamp. It can operate as low as 25 watts and as high as 80 watts, but is centered to us a standard 4 foot 32w fixture and it's own timer. It is four foot long, 1.5" in diameter, so it can be used in virtually every 4 foot fixture at the hardware store. Our entire goal was to make it simple and cheap to operate. All the really interesting things are happening inside the lamp, not in the fixture.

Again we licensed Sol Glass for this lamp, like our SG series lamps. It is more transparent to any other UV glass made, and allows transmission of UVB between 280nm and 300nm, something other lamps don't do well. This is one reason our lamps have been so successful in the labs, testing for resin/flavonoids/terpenes/THC. The new spectrum uses many of the same spectral peaks as the SG, but are 3 to 4 times stronger in the UVB, while still having a solid UVA profile. UVA is seldom discussed in many circles, and it is too large a topic to discuss here, but we design our lamps with a sun similar UVA spectrum because we have good reason to think it is also very beneficial for UV started plants. The UVA to UVB ratio is very different than the sun, however, as the effective ratio is about 4 times higher than the sun. This is why you can use half as many lamps and still get twice as much UVB. In short, you use few lamps farther from from your plants. This makes using them easier and cheaper for you, while being more effective. It is hard to overstate how big a leap this lamp is.

Like most Solacure lamps, the Flower Power has a built in reflector, so you don't need to worry about using reflective material with it. Mylar, white paint, all these absorb UV anyway, they are useless for reflecting it. The image on the left shows a regular lamp, the image on the right is how the Flower Power is designed, with an internal reflector. It forces all the light to go in one direction, making designing and installing a system much easier. This means the lamp has about 50% more total UV output than a non-reflector design with a home made reflector.

For all flowering plants (including fruits and vegetables) grown indoor or in a greenhouse environment. The exact amount of UV needed for each plant will vary, and must be determined by the grower. To offer enhanced UVB, most growers will use two of the Flower Power lamps for every 1000w HPS/MH or equivalent. Obviously these will work on cannabis and are designed to maximize the UVB needs of the buds, but it was designed to be a greenhouse light and to provide the missing UVB for any plant.

How to use these lamps
Use two Flower Power lamps per 1000w hood, one on each side for even coverage, 12" to 24" from the plants (farther is weaker so needs to be run longer, but covers a larger area). Run 1 to 4 times per day, 1 to 6 hours per cycle for up to 12 hours (single cycle). How much depends on your particular plants, so start with 2 to 4 hours and work your way up, looking out for burned edges. The goal is to stress the plants, push them, without damaging them. Only run during your day cycle. Use during flowering and fruiting stage. Also proven to suppress mold and mildew as well as discourage many insects.

Another method that is claimed to produce higher CBD is the "Pulse Method". You run them 15 minutes on, 45 minutes off. This will shorten lamp life somewhat, but will still get you 2 flowering seasons worth of use. These claims have been made by a few professional growers. Most tests that instead run the UVB continuously for several hours have shown to not dramatically affect CBD production (flat to slightly higher).

Already certified to get 20% to 35% higher THC and flavonoids and anecdotal evidence that approaches 40% higher, and results keep coming in.

We use them throughout the entire grow. Both veg, and flowering.

If vegging 18 hours, we let the HID come on for 3 hours before the UVA/UVB bulbs turn on. Then 3 hours Before lights ( HID ) out, the UVA/UVB bulbs go out.

On 12 hours.. 2 hours after HID come on, UVA/UVB comes on. Basically the UV is on 2/3 of the time regardless of veg/flowering.
If someone wants to TL;DR the wall of text above me feel free.

But, I'm still voting for the cheap bulb. It doesn't take much UV to get the job done.
There is info out there proving uva increased flavanoids in vegatables but only uvb is shown to increase thc. Its the plants defense against the harmful rays.

I have read tests that showed the same increase in thc 3-5% (ie;19% to 23% thc) with the uv on all the way through flowering and only the last 2 weeks. That grow now uses it only during ripening.

Sorry i dont have the link. I did this research over the last 4 years and saved stuff to old phones.

Hortilux sells t-5 flourescent tubes in various spectrums. The uv plus is a full spectrum vrow bulb and the pure uv is for supplementing.

Go easy uvb can burn plants, skin and damage your eyes.

Not worth it unless you are paid for higher thc in lab tests in my opinion. Higher thc does not equate to a better high.
After some research, I am going to add uvb lights.
question. Where to get a good light at.
2nd, when do I add it to the grow?
thank you
There are UV LED's or COBs that give you the choice of Near and Far UVA, UVB, and UVC in 10 to 50 watt sizes. One solution if you don't like LEDs, is to buy or make a fixture for a tanning bed bulb (fluorescent), although I would use a separate timer as I don't know how long you want to use it on a plant. The LEDs/COBs run up to about $35, smaller individual LEDs aren't too expensive, but you need a bunch of them. The larger COBs might work out better.
I'm running two 4' solacure bulbs this grow. I'm still in the first week of flower and don't plan on using them until week 5 or 6. I plan to start them out for an hour a day. I'll add an hour each week if possible, stress dependent. I'll have them come on mid light cycle so I don't have to be in the tent when they're on. The tent and the plants will be left alone during the time they're on.
i bought (2) HLG 36 UVA supplement lighting. that i use the last 3 weeks at 3hrs a day . and i have seen an increase in tricone production. this is my third run with HLG 36 UVA supplement lighting.
i bought (2) HLG 36 UVA supplement lighting. that i use the last 3 weeks at 3hrs a day . and i have seen an increase in tricone production. this is my third run with HLG 36 UVA supplement lighting.
This is my first grow but I am still going to give uvb a go and hopefully will get some good results
I hang 2 13w reptile (uvb) cfl bulbs in my grow. I start with them 20" or so away from the plants/canopy. They run 12/12 same as my LEDs. Later stages of flower I move them closer, to about 12" over. It's not a lot of uv...pretty low exposure over time. Nothing scientific, but you can see a visible difference in the amount of trichomes between those plants directly under it and those not...anyway, I'm not a pro...just growing on a shoestring budget...and after reading a couple actual studies, I figure any uvb is better than none.