Key Takeaways From Ed Rosenthal's and Surna Cultivation Technologies Instagram Q&A

Boulder, Colorado -

Surna Cultivation Technologies recently participated in a Q&A on Ed Rosenthal’s Instagram. They took to the comment section to answer growers’ questions about HVAC, humidity control, and mold and powdery mildew (PM) prevention.

Ed Rosenthal is a cannabis activist, author, and entrepreneur. He is best known for his work in advocating for the legalization of marijuana and developing cannabis-based products. Rosenthal has written several books on the subject of cannabis, including The Marijuana Grower's Handbook (2009), Beyond Buds: Marijuana Extracts, Hash, Vaping, Dabbing, Edibles and Medicines (2015) and most recently, Cannabis Grower's Handbook: The Complete Guide to Marijuana and Hemp Cultivation (2021).

Rosenthal is a strong proponent of the benefits of cannabis, and he continues to work to make it more available to people who can benefit from its use.

The first topic of discussion outlined the main causes of powdery mildew. Powdery mildew is one of the most common plant diseases. It can affect both indoor and outdoor plants, and it commonly appears as a white or gray powder on the leaves and stems.

Having high humidity or bringing in an infected strain will speed up the outbreak of PM in a facility. PM spores are all around us and are most likely brought into a grow via infected clones, on employees' clothing, or from unfiltered air that is brought into the facility. It's when the environment is unstable, or the plants become stressed that PM spores are able to germinate and grow on the plants.

The next topic of discussion covered the prevention mold in outdoor cannabis grows. A user asked, “What precautions can I take to prevent mold in an outdoor grow?”

Surna provided some simple precautions to prevent mold in outdoor cannabis grows: "Proper plant spacing is important to limit leaf wetness. By having plants that are spaced properly, you can prevent leaves from becoming too wet. This will help your plants stay healthy and avoid problems caused by excess moisture."

Surna also note that preventing mold and PM outdoors can be more difficult than in a well-designed sealed environment. This is because indoor growing gives growers total control over the climate and because they are not bringing in outside air along with its contaminants.

On the topic of CO2 Safety for Indoor Cannabis Growers, Surna had a lot to say. Surna commented that,”If a grower is not supplementing with bottled CO2, they will need to ventilate. (Although there are a lot of benefits to sealing it up and supplementing with CO2 instead). The plants will deplete the CO2 faster than one may think. However, it should be noted that this will expose the plants to whatever is outside, good or bad. Implementing an air sanitization system (like Air Sniper UVC technology) can help you get in front of potential risks.” Additionally, another user asked if a carbon filter is all that is needed for his intake or if he needs anything else. “A carbon filter is a great particle and odor filter, but it doesn't sterilize or filter out fungus or pathogens. Inline HEPA filtration or UV would be a great addition to your intake to protect that crop.”

While carbon filters can't remove all contaminants, there are other filtration and sanitization options available as well. HEPA filters are designed to capture very small particles, making them an essential part of any comprehensive filtration system. Growers should also be sure to regularly replace their filters to maintain optimal effectiveness.

Surna continued by explaining the benefits of UVC bulbs. “UCV bulbs sanitize the air by killing pathogens rather than filtering them out. It’s important to pay attention to the dwell times that different brands advertise, though. Insufficient dwell times will not allow the pathogens sufficient time to be exposed to the UV lights to be effective in killing them.”

The final topic covered in the discussion was, “What to Do About White Dust From the Humidifier?” One user commented they had noticed a white, powdery substance on the surfaces of his humidifier. Surna explained that it is most likely mineral deposits from the water used in his humidifier, and while it's not harmful, it can be unsightly.

Fortunately, reverse osmosis (RO) water should help, but RO does not remove all the minerals. Surna commented that it seems some are still in this user’s humidification water. Surna recommended was a steam humidifier, such as the Surna by Anden S35FP, which can use tap water and will not leave white dust on surfaces like an ultrasonic humidifier.