When it comes to UV, it’s all in the letters. UV has long been known to increase the quality and pigment of the plants, UV-A and UV-B are used most with indoor growing, however, as UV-C light is so destructive that one could go blind by simply looking at it. Even though UV-C has redeeming qualities, they don’t outway their destructive ones and it is really only good for sterilization and for the creating of ozone for smell masking.
UV-A vs. UV-B: Who’s the Boss?
UV-B is built right into some LED grow lights, so they must be good, right? That’s not the full story... Though these companies claim UV-B rays as prominent in the atmosphere, in all actuality the sun itself only puts off about one sixth of one percent of UVB light. On the other hand, UV-A is well over 2 and 3/4 of the photons that come through our atmosphere inside sunlight. Almost 20 times that of UV-B. Even with weather and clouds, small amounts of UV-A will almost always certainly come through.
Though both UV-B and UV-A in LED lights produce more oils, resins and overall better appearances, UV-B causes more damage to plants. Damage that sometimes outweighs the benefits. UV-B is also the main culprit in skin cancer in both humans and animals because of its shorter wavelength that stops right around the outer layers of skin and start burning in. With plants, UV-B radiation precipitates DNA damage resulting in cell arrest and can even lead to cell death.
If you still do decide to go the B route (UV-B is often found in florescent bulbs and even in some LED grow lights), you must wear protective gear such as sunscreen, long sleeves and sunglasses. Having UV-B in an LED actually makes no sense though, as those bulbs must be 6-8” from the canopy, while the LEDs should be more like 1-1.5’ from the canopy. Plus, those florescent bulbs produce UV no longer after just 2000 hours, while UV-A LED diodes will last for 50,000 hours. Sunglasses and long sleeves are always a good idea under powerful grow lights, though, with UV or otherwise.
Another reason to tread lightly with UV-B is that it’s very “energetic” and can cause cancer, however, the Earth’s atmosphere blocks most UV-B rays, as previously stated. This is the reason that tanning booths are so dangerous! Fluorescent bulbs that produce UV are pretty much the same tubes that get you that great orange glow from the tanning bed, as are reptile bulbs! Always do your research.
While both UV-A and UV-B are known to increase flavonoids, terpenes and add antioxidants, UV-A is known to be far less harmful to plants. Plus, it’s far more beneficial and easy to use. BloomBoss LED lights come with an all UV-A “Boss” switch that can be used at every stage of growth, depending on the plant and strain.
Once flipped, the switch lights up all LED UV chips for longevity, penetration and radiation (yep, we care). Our UV-A can be turned on from seed to flower if desired, though to each their own. Some experimentation and strain knowledge is helpful here.
As previously stated, some growers do use it full cycle, but this all depends on strains and phenotypes of plants. With some strains, having UV during veg is a great idea. Especially if you know that strain is accustomed to mountainous regions, where there is more UV light, rather than plants that grow in lower sea level areas. Some people only use the UV switch in the second half of flowering for oils and appearances, but people have had great success with the UV switch in every varied way utilized. That’s why we put a seperate switch: to give you the power!
With the BloomBoss UV-Boss Switch you can expect deepened purples, frostier coatings, greener greens, bigger flavors and denser, more potent flowers. Right now, BloomBoss is in the middle of a study to see how UV light effects catnip’s potency, terpenes and flavinoids. Stay tuned for pics and results! (The below captured catnip is lit up under UV light alone and it gives them a pink glow.)