With regulations for the use of pesticides becoming stricter by the day, greenhouse growers have fewer tools available to keep their crop healthy in a responsible way. Especially for problems with powdery mildew, growers are eagerly looking for new innovations that either outperform current solutions, or can replace crop protection products that have been strictly regulated or outlawed.
One of the methods that many growers are now adopting is treating their crops with UV light. According to Shane Hutto from Horticultural Solutions, this method gets more popular by the day as growers are achieving good results with it.
"Since states like Colorado are regulating pesticides and recalling products, many growers approach us with their problems. We knew that many professional Dutch greenhouse growers have been successfully tackling their mould problems with UV technology for a couple of years now, hence we wanted to introduce the technology over here as well."
Herbs treated with UV light in a commercial greenhouse
Horticultural Solutions approached the inventor of the technology, CleanLight, in order to set up several trials at North American growers. Hutto explained that almost every grower that applied the CleanLight method immediately achieved good results in the trial stage.
"We have done a lot of trials. All of the growers that we have worked with have seen positive results. Some really love it and some wanted to do more trials, but overall every grower we have installed a UV treatment system for has come back to us and bought more installations."
Appplication of preventative powdery mildew treatment in medicinal crops.
According to Hutto, the investment of the CleanLight system can be easily earned back, within a year, as expensive chemical crop protection is no longer needed. This results in a better workflow at the company as the products can be harvested without a waiting period as the crop is not contaminated with residues. In addition to this, less labor is needed to apply preventive action against powdery mildew.
The CleanLight method is sustainable and organic; the dose of UV light is high enough to kill most moulds and low enough that it does not do any damage to the crops.
Automated boom with UV lamps attached
"We design and manufacture special boom installations with the CleanLight UV lamps attached. The booms run automatically back and forth over the crops and can apply a dosage of 10-30 seconds of UV light per plant. This is totally automated, very exact and requires less manual labor.
Horticultural Solutions also has these handheld units available for treatment of crops in smaller and hobby settings.
While the CleanLight method now finds great acceptance in the medicinal marijuana industry, the technology is also used commercially by progressive greenhouse growers in the Netherlands in tomato, cucumber, green peppers and rose crops. Hutto said that he is running trials with food crops in the U.S. as well.
According to CleanLight, the UV treatment has proven to be effective on a variety of crops, inlcuding Mycaspharella and powdery mildew on cucumbers, Botrytis on tomatoes, Fusarium on green peppers and Powdery mildew on roses.
The method is approved as a treatment for USDA Organic certified products.