Adding UVB spectrum to COBs - opinions on this setup?

Abiqua

Well-Known Member
A metal halide light produces UV-B light if you remove the glass from your reflector and you don't need to hang them so low you can put them between HPS , that's what I do in my HID grow and in my LED grow I use an LED with a UV-B dongle 18% UV-B light.
Have you ever had any samples lab tested Yoda? Any terp profiling done?
 

Abiqua

Well-Known Member
Defense Proteins
When plants are hit with ultraviolet light, this event triggers the plant's defense mechanisms. The plant then becomes more resistant to insect attacks as it releases 15 defense proteins. The ultraviolet light also affects message pathways that impact plant development, growth and metabolism, according to Washington State University. The ultraviolet light tricks the plant into thinking that it is wounded, which occurs when the plant is being feed on by insects. However, the ultraviolet radiation does not help the plant compete with weeds, according to Plant Cell.
The study you are referencing, never referenced Cannabis.......
 

Yodaweed

Well-Known Member
The study you are referencing, never referenced Cannabis.......
Cannabis is just another plant, I use a lot of the same techniques to grow my tomatoes and peppers as I use on my cannabis, it's just another plant. I do have some articles on cannabis if you would like me to paste them but they same basically what I just said and what that article I linked says. Just google UV-B on cannabis or UV-B on plants and you will find a wealth of knowledge.
 

researching

Well-Known Member
Defense Proteins
When plants are hit with ultraviolet light, this event triggers the plant's defense mechanisms. The plant then becomes more resistant to insect attacks as it releases 15 defense proteins. The ultraviolet light also affects message pathways that impact plant development, growth and metabolism, according to Washington State University. The ultraviolet light tricks the plant into thinking that it is wounded, which occurs when the plant is being feed on by insects. However, the ultraviolet radiation does not help the plant compete with weeds, according to Plant Cell.
Interesting.... so jasmonate and UV work similarly.
 

Shugglet

Well-Known Member
Cannabis is just another plant, I use a lot of the same techniques to grow my tomatoes and peppers as I use on my cannabis, it's just another plant. I do have some articles on cannabis if you would like me to paste them but they same basically what I just said and what that article I linked says. Just google UV-B on cannabis or UV-B on plants and you will find a wealth of knowledge.
No, you dont. You get links to a bunch of forum threads like this.

I love the "cannabis is just another plant" comment. Sure, but it also has a very unique property of psychoactive chemicals, which are really the only part we care about it this discussion.
 

Yodaweed

Well-Known Member
No, you dont. You get links to a bunch of forum threads like this.

I love the "cannabis is just another plant" comment. Sure, but it also has a very unique property of psychoactive chemicals, which are really the only part we care about it this discussion.
It's not special, it's just another plant , lavender has trics too, you just are a novice gardener and only have experience with 1 plant. Open your horizons maybe you will learn something. There's PLEANTY of other plants that can get you higher than weed, just go smoke some refined poppy and let me know how you feel.
 

MeGaKiLlErMaN

Well-Known Member
doesnt the glass on the HPS lamps block UV radiation?
Moderately but theres not much there to begin with.. Im talking DE HPS not standard they probably have less that a DE. So the glass thats used for a plant growing light shouldnt be blocking itself... that would be a terrible design.
 

Shugglet

Well-Known Member
It's not special, it's just another plant , lavender has trics too, you just are a novice gardener and only have experience with 1 plant. Open your horizons maybe you will learn something. There's PLEANTY of other plants that can get you higher than weed, just go smoke some refined poppy and let me know how you feel.
The other part of my response was more important to this topic anyways. There isnt a lot of research in this field, hence the debate. If you could point to me some scientific articles thatd be cool.
 

Yodaweed

Well-Known Member
The other part of my response was more important to this topic anyways. There isnt a lot of research in this field, hence the debate. If you could point to me some scientific articles thatd be cool.
It is best to stay safe and not take any risk with poorly controlled experiments. It is scientifically proven that the amount of UV-B rays a plant receives may increase the production of trichomes.

UV-B rays are harmful to other plants (and humans if applied in large quantities), but when cannabis plants receive a large amount of this type of ultraviolet rays, the trichome count can be increased.

We can use this method to greatly increase the amount of trichomes of cannabis plants and thus the amount of cannabinoids.

The lamps we use for the flowering cycle in indoor cultivation called HPS (High Pressure Sodium Vapour) have acceptable levels of UV-B, but are harmful to humans if we are a short distance from the lamp; they are acceptable for cannabis plants . The lamps we normally use for the growth stage of these plants called MH (Metal Halide) lamps emit a much greater amount of UV-B rays than HPS lamps.

This means that if you want to increase the production of trichomes of a plant, just replace HPS lamp by MH during the last two weeks of flowering. This will create increasing levels of UV-B radiation and thus cause the plants to produce good quantity of resin (trichomes).

Some might wonder then why not use Metal Halide lamp all through the flowering cycle. The answer is simple; it is not recommended by the light spectrum. HPS lamps have a much redder spectrum, which is ideal for the development and maturation of buds. On the other hand, MH lamps have a more bluish-white spectrum, which is ideal for the growth stage (development of branches).

By changing the bulb during the last two weeks, you can help the plant create more trichomes and thus be more powerful. There are also specific bulbs emitting UV-B rays, but due to their high price it may not be profitable in cultivation medium.
In outdoor cultivation, things change a lot; we cannot control the temperature and humidity, though we can control the level of nutrients that the plant receives. So, we need to take some extra efforts to add specific fertilizers during different cycles. This will create a more balanced and therefore higher quality plant.

If what you seek is an explosive production of trichomes, you must follow outdoor cultivation on high mountain peaks. At higher elevations, the UV-B radiation from the sun increases and so a plant of the same gene grown outdoors on the top of a mountain to a considerable height will be much the same resinous plant cultivated at sea level for example.

If you opt for this trick to grow on high mountain, then keep in mind that you must measure the room temperature because if it’s frosting then it’s useless even if cultivating at greater height. It is important that the temperature and relative humidity is acceptable.


http://marijuana.tm/en/thc-and-uv-b/
 

Shugglet

Well-Known Member
It is best to stay safe and not take any risk with poorly controlled experiments. It is scientifically proven that the amount of UV-B rays a plant receives may increase the production of trichomes.



http://marijuana.tm/en/thc-and-uv-b/
If it were "scientifically proven" the word "does" would be used instead of "may". No?

I should note Im not saying that UVB doesnt have any impact. Im just questioning the degree of impact it has and whether or not that degree makes it worth adding UVB light or not.
 

Airwalker16

Well-Known Member
It is best to stay safe and not take any risk with poorly controlled experiments. It is scientifically proven that the amount of UV-B rays a plant receives may increase the production of trichomes.

UV-B rays are harmful to other plants (and humans if applied in large quantities), but when cannabis plants receive a large amount of this type of ultraviolet rays, the trichome count can be increased.

We can use this method to greatly increase the amount of trichomes of cannabis plants and thus the amount of cannabinoids.

The lamps we use for the flowering cycle in indoor cultivation called HPS (High Pressure Sodium Vapour) have acceptable levels of UV-B, but are harmful to humans if we are a short distance from the lamp; they are acceptable for cannabis plants . The lamps we normally use for the growth stage of these plants called MH (Metal Halide) lamps emit a much greater amount of UV-B rays than HPS lamps.

This means that if you want to increase the production of trichomes of a plant, just replace HPS lamp by MH during the last two weeks of flowering. This will create increasing levels of UV-B radiation and thus cause the plants to produce good quantity of resin (trichomes).

Some might wonder then why not use Metal Halide lamp all through the flowering cycle. The answer is simple; it is not recommended by the light spectrum. HPS lamps have a much redder spectrum, which is ideal for the development and maturation of buds. On the other hand, MH lamps have a more bluish-white spectrum, which is ideal for the growth stage (development of branches).

By changing the bulb during the last two weeks, you can help the plant create more trichomes and thus be more powerful. There are also specific bulbs emitting UV-B rays, but due to their high price it may not be profitable in cultivation medium.
In outdoor cultivation, things change a lot; we cannot control the temperature and humidity, though we can control the level of nutrients that the plant receives. So, we need to take some extra efforts to add specific fertilizers during different cycles. This will create a more balanced and therefore higher quality plant.

If what you seek is an explosive production of trichomes, you must follow outdoor cultivation on high mountain peaks. At higher elevations, the UV-B radiation from the sun increases and so a plant of the same gene grown outdoors on the top of a mountain to a considerable height will be much the same resinous plant cultivated at sea level for example.

If you opt for this trick to grow on high mountain, then keep in mind that you must measure the room temperature because if it’s frosting then it’s useless even if cultivating at greater height. It is important that the temperature and relative humidity is acceptable.


http://marijuana.tm/en/thc-and-uv-b/
Wonderful Info. But did you read this thread? Literally all of what you said was all gone over lol.
 

Yodaweed

Well-Known Member
I really want to do an outdoor grow , I live at over 6500 ft altitude, the US Olympic training center is less than a mile from my house , the amount of UV I get on a regular basis is insane , generally UV levels are above 10 and sometimes push upwards of 16.
 

researching

Well-Known Member
If it were "scientifically proven" the word "does" would be used instead of "may". No?

I should note Im not saying that UVB doesnt have any impact. Im just questioning the degree of impact it has and whether or not that degree makes it worth adding UVB light or not.
I would add, with no scientific merit, that hash making regions tend to be higher in uv rays. Obviously we know where hash comes from. So I would agree with an earlier statement that genetics is primary and I believe that UV is a pontentiator. Only based on basic theory and circumstantial commonalities.
 
Last edited:
Top