How Does UVB Affect Terpenes & Improves Harvest Quality

Many grow light manufacturers now include UV lights in their full-spectrum products. They're not as dominant compared to red, blue, or white spectrum LEDs, but they do play an essential role in growing indoors.

There are two kinds of UV lights, UVA and UVB, which have this effect on terpene and harvest development. To help you understand what you can get from UVB lights, here's what you can expect from these LEDs.


What are UVB Lights? 

California Lightworks SolarSystem 550 UVB Full Spectrum LED Grow Light

UVB Lights are a type of light that delivers UVB, or ultraviolet B rays. This light has a wavelength ranging from 29 – 320 nm. In natural lighting, UVB lighting is a tiny percentage of the composition of sunlight. It might have harmful effects, but the ozone layer filters it to ensure that the amounts that get through are not damaging.

Grow light manufacturers have found a way to replicate UVB lighting for indoor cultivation. Because of this technological advancement, grow lights can emulate natural sunlight realistically.


How do UVB Lights affect Terpenes and Harvest Quality? 

UVB lights ensure that your buds will have higher-quality terpenes. While terpenes still develop even without UV lights in general, the result could have been better; while crops grew, it was discovered that some terpenes were missing when UVB lights were not used.


MIGRO ARAY 12 Full Spectrum LED Grow Light

Dutch Passion conducted parallel tests between using and omitting the UVB lights; using the Migro UVB-310, plants that grew under UVB lights had an average of 20 percent more terpenes than plants that didn't grow under UVB lighting. The results were remarkable that plants had as much as 50 percent more terpenes available.

Terpenes matter because they are responsible for your buds' flavor profile and aroma. It's what makes a bud more pleasing when presented at a dispensary. Not having enough terpenes mean that the buds will lack flavor and have no distinct aroma.

Having a high amount of terpenes present means that the bud is of high quality and reflects the horticulture skills of any grower. If the terpenes present are full of aroma, it would mean the bud is flavorful, and from a grower's point of view, that means you can charge a premium for a flavorful harvest.

Using UV lights, in general, also improves root development and vegetation. As a result, you get a much heftier harvest. When introduced early in plant development, UV lights can help speed germination while adapting to light intensities.

Now, UVB lights don't just improve terpenes and harvest quality. They also add a layer of protection for your plants during their development. When exposed to UV light, plants generally produce defense proteins that help combat microorganisms, fungi, insects, and bacteria that can affect your plant's development.

Speaking of flavor, adding UVB lights also improve oil and resin production from your buds. You can imbue more robust flavors and aromas when used in different applications. Now terpenes don't affect the potency of a bud, but just the same, introducing UVB lights early will also improve the potency of the buds.


Improving Terpenes 

Using supplemental UV lights is just one aspect of improving the terpenes on your harvests. Even if you use high-quality seeds for planting, other factors should be considered in enhancing terpene content.

One thing to consider is how much light your plants are getting. Start with a high-quality grow light, such as LEDs. You must also identify the lighting situation and fill the gaps with supplemental lighting.

The kind of nutrients you use also matters in terpene development. Organic nutrients provide many benefits in terpene production, but they must be balanced, as this can cause stress on your plants.

Once buds start growing, you should project when to harvest. Harvesting too early will not allow the terpene content to develop fully while harvesting too late will degrade the buds. And once you harvest, knowing how to cure your buds properly will ensure that terpenes are properly preserved.



Terpene development relies on many factors, and the grow lights you use are one critical factor to consider. While you can use standard full-spectrum, grow lights, adding UVB lights can help spur terpene development further. If you're looking for ways to improve your harvests, consider adding UVB lights to your setup.