Fighting pathogens through germicidal UV-light

Since 2008 CleanLight B.V. has been fighting and controlling diseases in the horticultural industry with germicidal UV-light. The main markets are cut flowers, strawberries, vegetable young plants, herbs and flower bulb productions. In 2012 the first recreational cannabis growers started using CleanLight to fight Powdery Mildew and Botrytis in an organic way. In the last three years some of the largest licensed medical marijuana producers in Canada and in the US have started to integrate CleanLight in their IPM.

Crop protection is a big issue within the medical cannabis industry. In Canada, for instance, growers cannot use any chemical product to fight disease like powdery mildew and botrytis. “Powdery mildew and botrytis are parasites, they suck energy out of the plant, which results in lower yields and slower growth. If you have powdery mildew in your cannabis, it becomes difficult to sell. In the medical market, your product would get rejected,” Arne Aiking, owner and founder of Clean Light, explains. “The regulatory environments do not allow growers to use any chemical crop protection, and therefore they face many challenges when they have to get rid of diseases, such as those. This is why we developed a solution that does not use any chemicals.”

That is why CleanLight solutions, according to David Symanzig, account manager for North America, uses a special type of UV light which, if applied consistently over time, not only kills fungi like powdery mildew and botrytis, but also makes the plants stronger so that any future disease can be prevented by the plant’s defenses themselves. “We use a different type of UV light, and we use only 1% of what is normally used for disinfection,” David explains. “Since we only use a tiny shock, it is safe for people, for plants and for beneficial insects. But it does kill powdery mildew and botrytis.” However, David takes care to remark that CleanLight’s objective is not only to kill plant diseases but also and mainly to reinforce the plant. “The primary goal is not so much to kill the fungi, but to make the plant stronger,” he says. “If a cannabis plant grows outdoors, it gets a nice dark green color. If it grows indoors, it gets no UV, and the plant suffers from a chronic shortage of UV. We restore the natural diet of the plant. If you give your cannabis plant a tiny bit of UV every day, the plant becomes strong and able to defend itself against diseases.”

CleanLight UV crop protection comes in different solutions. "There are three main systems," Arne says. "Firstly, the handheld systems which are suitable for small growers and operations. Secondly, the hand-cart system as seen in the video above, these come in all different varieties and measurements. Only with vertical units or also with horizontal arms which go over the top of the canopy. Lastly, the largest growers often have irrigation booms and mount the CleanLight modules on them or install purely CleanLight UV-booms. Growers run these booms around the facility, and therefore the system becomes automated."

According to Arne, the concept behind the CleanLight solution is based on the fact that marijuana plants within indoor environments, either a greenhouse or an indoor farm, “suffer from chronic shortage of UV.” Therefore, the CleanLight solution provides the plant with a specific dosage of UV rays in order to restore the natural diet of the plant. However, UV rays can be dangerous, and Arne knows this very well. “We apply an extremely low dosage of UV light. Many growers are familiar with UV lights. For instance, it is used for water disinfection – this tech is called UV disinfection. The UV is used to kill everything in the drinking water, and it works. But if you use the same amount in a greenhouse, you kill literally everything – powdery mildew, beneficial insects, and the plants themselves – and it could cause serious health problems to employees,” Arne explains.

These systems are sophisticated, that is why CleanLight closely follows its customers in order to thoroughly explain every small detail of the technology and train the growers in using the CleanLight crop protection method. Additionally, CleanLight works with distributors, local dealers and boom manufacturers to offer the best service and guidance possible.

"Next to the crop protection technology, CleanLight also provides UV air purification systems, UV water disinfection and UV post-harvest installations. These installations are mostly custom made," Arne concludes. 

For more information:
CleanLight B.V.
David Symanzig – Account manager North America
(415) 527 0887  


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