August 14, 2021
Many growers misunderstand ultraviolet light. They think that it will always hurt their plants. Or, they think that only UV-B is helpful in increasing the medicinal quality of plants. Both those statements are untrue. In this article, we’d like to tell you four reasons you should be growing with UV-A.
UV is electromagnetic radiation just beyond visible light in energy but lower in energy than x-rays. They range from 400 nm to 10 nm (which is a greater wavelength diversity than visible light, ranging from 400 to 700 nm). For plants, there are two relevant types of UV: UV-A and UV-B. UV-A is the lowest energy UV and ranges from 400 nm to 315 nm. UV-B is higher energy than UV-A and ranges from 315 nm to 280 nm. At sea level near the equator, 6% of solar radiation is UV — 5.7% is UV-A and 0.3% is UV-B. Depending on latitude, elevation, and time of year, plants receive 10 to 100 times more UV-A than UV-B. Higher energy UV light, such as UV-C, is filtered out by our atmosphere and doesn’t reach Earth’s surface. (And thank goodness! UV-C is quite dangerous to live organisms.)
UV light is highly energetic, so it can cause damage to living tissues.
Around 3% of sunlight is UV light, so most plants are exposed to UV radiation in their natural habitats.
To shield themselves from the harmful effects of UV lights, plants will activate specific processes and produce certain molecules that have protective functions, such as repairing damage or absorbing UV light.
For indoor plant growers, these processes and molecules are useful in improving the quality and yield of plants.
UV light is a range of wavelengths stretching between 100 to 400 nm. This range is divided into smaller wavelength ranges (UVA, UVB, and UVC). In indoor gardening, UVA (315–400 nm) and UVB (280–315 nm) are mainly used.
There’s a lot of debate going on about whether UVA or UVB is better for plants.
Atreum Lighting UVA Light Bar, 30W (2-FT)
Features:
The Atreum Light Bar provides 30W of 385nm UVA supplementation in a compact and easy-to-use package. The light is basically a 24-inch-long LED bar that contains 385nm diodes (in the range of UVA light). The device draws around 30 watts of power only, so it won’t cost you a lot of energy. It’s also waterproof, so it’s great for humid growing environments. The grow light is very affordable taking into account that UV lights are usually expensive. Although this is UVA light, take the necessary precautions and follow the manufacturer’s guidelines while using HLG 30 UVA supplement in your growing environment.
TotalGrow UVA Bar 30W LED Grow Light Bar
Features:
TotalGrow light bar is another great UVA light for plants. The UVA grow light is monochromatic with a spectrum of 385 nm (high UVA). TotalGrow UVA bar has a UVA output of around 40 µmol/s, and it can cover a 2’ x 4’ (0.6m x 1.2m) growing space. It draws around 30 watts, so it has an efficiency rate of around 1.3 μmol/J. The minimum recommended hanging height for this light is 24 inches. TotalGrow UVA is waterproof and has a daisy chain feature that allows you to connect up to 24 to 48 units together (depending on the voltage). The light has a 30,000 lifespan and comes with a 3 years warranty.
The effects of UV light on plants is a highly investigated topic with research spanning decades. Why is there so much research on this topic? Greenhouses primarily. Agriculture within greenhouses is a multi-billion dollar industry and most greenhouses are UV deficient because the most common material that covers greenhouses block UV, such as glass or polycarbonate.
Much of the initial studies on the effects of UV confused the subject. These studies only used parts of plants — chloroplasts or thylakoids — and not whole leaves or by tracking a plant's growth over time. These incomplete studies wrongly gave UV a reputation that it didn’t deserve and underestimated the ingenuity of plants that have become highly adapted to UV. Below is a sampling of research that tells the complex, multifaceted, and often species dependent responses to UV
Analogously to how little bit of UV can be good for humans since it helps us produce Vitamin D, so plants also respond to low dose UV by producing antioxidant compounds like flavonoids and phenolic compounds (incidentally, these compounds give fruit and vegetables their vibrant purple, red, and blue colors). Luckily for us, it just so happens that many of these compounds are powerful antioxidants and are very healthy to eat. Flavonoids have been highly correlated with living longer, weighing less, having a healthier heart, lowering cancer rates, and avoiding neurodegenerative disease. Other phenolic compounds play important roles in cancer prevention and treatment.
UV light is harmful to humans. It can cause skin damage and cancers. You should use UV lights in an enclosed growing space and wear protective material while working around or under them.
Exposing your plants to UV light for long periods can harm them. For this reason, you need to keep it on for few hours a day only. Stick to the manufacturer’s recommendations to know how long you should keep the light on each day.
Keep enough distance between your plants and the light to avoid damaging them.
Don’t use any UV light for your plants. Some UV lights can be very intense, and they can destroy your growth.
UV lights can help you improve your growth and yield.
However, you need to know how to use them properly, or else you could damage your plants.
Always follow the recommendations by the manufacturer and do your own research before using UV grow lights.
You can also test your UV lights with different plants before using them with your main crop.
And finally, we cannot overemphasize the importance of taking the necessary precautions while working around these lights.
Happy growing.
June 27, 2024
When choosing Best LED Grow Lights, you should also consider the durability of the lamp, energy efficiency and whether it can meet the light needs of specific plants. For example, the LED plant growth lights provided by Philips Lighting are designed for specific crops to promote uniform growth and improve quality and yield.
June 20, 2024
June 15, 2024
On Amazon, hot growth light types include LED Growing Lights, which have a variety of functions and features such as automatic on/off timing, red and blue LED light combinations, multiple dimmable modes, and flexibility for indoor potted plants or indoor gardens.