Harnessing Nature: UV Light and Its Surprising Benefits to Cannabis Operations

Ultraviolet light (UV) is a growing method to reduce pests' impact, increase THC content, and accelerate the growth process. Artificial UV light allows growers to improve comparable plant quality of indoor cultivation without adding expensive synthetic chemical fertilizers.

What is Ultraviolet Light?

Ultraviolet is a type of light that is not visible by humans. UV light is composed of three sections: (1) UV-A, (2) UV-B, and (3) UV-C. On a typical sunny day, the average plant can expect to receive about 95% UVA and 5% UVB light. Note that UVC light does not occur in natural conditions.

UV-Light-Effects-on-Cannabis-PlantsHow Does UV Light Impact Plants?

Plants evolved for millions of years under natural lighting conditions, domesticated for several tens of thousands of years, and growing under artificial light conditions for only about a century. The natural responses plants developed are triggered by natural light and environmental conditions to which they are no longer exposed in modern growth operations. The net effect of these artificial conditions is a decline in quality and quantity.

Benefits of UV Light

Growers can mimic natural conditions using UV light to trick indoor domesticated plants into reacting as if they were still wild.

UV Light Reduces the Impact of Pests

Plants are not static. Plants take in information from their environment and react. For example, certain UV wavelengths trigger plants to release defensive compounds to repel pests and alert other plants that predators are nearby. The defensive compounds make the plant less desirable to pests but enhance the taste, color, and THC and CBD concentrations. Essentially, a grower can "trick" a plant into becoming more aromatic and flavorful by using UV light.

Some studies also indicate that a combination of UV-B and photosynthetically active radiation (PAR) can trigger greater concentrations of defense compounds - including in older plant leaves. These increased concentrations deter whitefly and thrips, which are particularly pernicious pests that favor older plants.

Increase THC content

When a person is exposed to UV light, they develop a tan that is a natural shield to UV exposure. Similarly, plants release their own version of natural sunscreen. Cannabis produces higher densities of trichomes that shield the plant from UV light and store THC and CBD. Therefore, the increased density of trichomes also increases THC and CBD density.

Speed up Germination Process

UV light also accelerates the germination process - i.e., when seeds take to the soil. Growers can prepare plants for high-intensity light by shifting seedlings to more intense light sources. UV exposure in the early stages of growth reduces shock time which speeds up the growth process.

Cons of UV Light


While incorporating UV lighting does result in long-term cost savings due to reduced nutrient costs, there is a high upfront cost. Growers may need to rewire their lighting system to accommodate the new UV lights. Further, UV lamps are expensive.

UV Light Linked to Lower CBD Concentrations

Some studies link increased UV exposure to reduced CBD concentrations. Researchers hypothesize the reduction is due to a tradeoff in resources - as THC levels increase, CBD levels decrease. However, the silver lining to these studies allows growers to experiment with different CBD and THC concentrations. Growers can grow plants for specific products for either THC or CBD benefits.

UV Grow Lights Empower Growers to Harness Nature

On balance, UV light allows growers to harness natural processes honed over millions of years of evolution, increasing the quality and quantity of their crops while saving money long-term and reducing the impact of synthetic fertilizers and nutrients.

TSRgrow Announces New UV Light Bar

At TSRgrow we are continually researching new technologies to incorporate into our TOTALgrow Solution. Keeping in mind sustainability and efficacy when developing new products for our growers is always at the forefront of our process. Creating a UV light bar for our growers has been an exciting adventure and we are happy to be sharing this new product with you.

Our new UV light bars seamlessly integrate into our pre-existing TG-100HVR LED lighting used in indoor vertical growing. Combining these two lights will provide our growers with amazing and efficient plant growth.

Ask About Our New UV Light Bars


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