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TOP Misconceptions about growing with UV and Far-Red:

Do UV and far-red light actually contribute to photosynthesis?

YES! The important point to note here is that, when UV-A and far-red are supplied in conjunction with regular PAR light, photosynthesis increases.

Far-red light contributing to photosynthesis

Far-red is only useful just before lights out?

Far-red radiation, when applied in isolation for 15 minutes before lights out, can be a useful cue for some plant species to start flowering, but it can also increase photosynthetic rates, flower sites, and flower density when applied with PAR light during the regular daily cycle.

Greenhouse during day

UV is damaging to plants?

UV is a broad category of radiation so it depends on what sort of UV is being referred to here. At the high energy end of the UV range (E-UV / X-UV, UV-C) UV can be very damaging to living cells. Fortunately for all living creatures here on Earth, the ozone layer protects us from these harmful photons emitted from the Sun. A moderate amount of UV-A, when supplied in conjunction with PAR, can be beneficial. It can strengthen young plants, ward off pests and molds, encourage compact growth patterns, as well as stimulate the production of essential oils and terpenes. The iLogic8 full spectrum+UV+IR only emits this benign form of UV (UV-A, not UV-B or UV-C).

UV damages eyesight?

It’s all about common sense and protection—otherwise, we would never venture outdoors! Whatever grow light technology you prefer, it’s a bad idea to stare at your lights! Always wear sunglasses with UV protection when working with any type of grow light—including those which output some UV. Remember, the iLogic8 full spectrum+UV+IR emits the safer form of UV known as UV-A.

Far-red LEDs are dim and weak?

Careful! The human eye’s ability to see colors peters out in the far-red zone, so—while far-red LEDs may appear dimmer than their red and white counterparts—they are extremely powerful when it comes to driving photosynthesis in plants. DO NOT STARE AT FAR-RED DIODES! Always wear sunglasses when working in your grow room and consider dimming your grow lights when spending extended time with your plants.

Far-red is only good for flowering, not for veg?

Actually, far-red during the vegetative growth phase can encourage bushier plants with more flower sites, as well as stimulate faster growth.

Far-red will elongate plants and make them tall and gangly?

When a leaf of a light-loving plant is shaded, it naturally receives more far-red than red light, leading to stem elongation as part of the plant’s effort to avoid shade. When more red light is supplied than far-red, there is no additional stem elongation effect as the plant senses it is receiving sufficient direct light. The ratio of far-red to red light is carefully calibrated in LED fixtures to provide all the benefits of far-red without unwanted stem elongation.

Is it true that you’re sacrificing CBD when using UV light to bump up THC levels?

Yes. Both cannabinoids, CBD and THC, are derived from the “mother cannabinoid” Cannabigerol (CBG). Genetic and environmental cues will lead the plant to convert some of its CBG into CBD and some into THC, so if additional CBG is converted into THC, there is less CBG to be potentially converted into CBD.


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