Is Powdery Mildew all YOUR fault?

powdery mildew

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Something I hear quite often…

“Hey Max, I don’t get it?!  The temperature and humidity of my indoor grow are perfect.  I have great air circulation and I even bought an expensive HEPA Filter for my intake ventilation. So, how in the hell am I still getting powdery mildew in my grow?”


Have you considered taking your clothes off? I’m not being cheeky here… I’m being totally serious.  

You can take every preventative action within your grow to prevent PM, but a lot of people totally forget about the fact that they can easily be the culprit for having a PM infection in their grow.

The microscopic spores of PM travel easily and can stick to your clothing, body, and hair.  If you are exposed to the same strain of PM that can infect cannabis from another plant or person, and then walk into your grow, you’re putting your grow at risk.  Simply walking down the sidewalk next to plants with PM can be a recipe for disaster!

Interestingly enough, PM spores don’t require high moisture for germination.  Therefore, if your grow is in perfect shape and you bring PM into it, it can easily spread and thrive in what you would normally consider a bad environment for PM.

Back in the day, growers didn’t want people in their grow because it was illegal.  Today, many growers don’t want people in their grow because they don’t want to risk exposing their investment to diseases.  This is why many cultivation facilities have been using Personal Protective Equipment (PPE) wayyyy before Covid19.

In order to enter many grow rooms, PPE like onesies, booties, hairnets, beard guards, gloves, and (now) face masks are required.  The cost of the PPE comes nowhere close to the loss of disease destroying a grow.

Powdery mildew generally infects the leaves of plants first.  The leaf photo below has a very mild case of PM and can be easily taken care of.




Powdery Mildew is Lactose Intolerant


That’s right, the common fungus that can destroy an entire grow is allergic to milk. According to research at the University of Adelaide in Australia, milk can reduce PM disease to a level comparable to sulfur, and is an organic solution to a major problem.  

There are many strains of PM that affect various types of plants differently.  However, watered down milk has been utilized by many growers to stop PM in its tracks.  


Recipe options:

  1. A 1:10 ratio of organic whole milk to water (based on University study). 
  2. Another option that I have used is to mix 1 gallon of water, 2 oz whole milk, and juice of ¼ lemon. 

Spray on the infected leaves to stop the PM before the flowering cycle.  Don’t spray dried and cured flower with anything!  There’s no removing the PM at this point! 


1-1 2

dark knight STORAGE MOLD (2)


Do you know how to spot PM on finished flower?  Use our UV magnifier and the PM will light up like crazy!


Screen Shot 2020-09-29 at 2.14.20 PM


So the next time you go into your grow, think about where you’ve been, what could be on you, what PPE you have, and if you have milk in the fridge!



Max at Trichome


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