Powdery mildew - An easily exterminated parasite

Yes but know I remember I hit it with some need oil as well….lol it’s been a long time but I certainly remember the triangle kush having white fluff all over the stems and bud sites(I had only one oscillating fan at the time) also had spider mites years ago but been oil really seem to help

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Sounds like it was probably penicillium instead of powdery mildew from your description. Can’t go back in time and make sure!
I’m slowly growing those little plants, and I am pretty sure two of them are invasive wild asters. Observe!





The wild asters don’t have leaf serrations! You can see the fat serrated leaves on the white asters. I’m starting to think they need more light to grow faster. Put them off to the side, but now there are real tomato seedlings in there that will need more light.

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I watched a guy who grows blue berrys he uses spoiled milk for powder mildew its the bottom layer of the milk enzymes kill the mold I believe not sure why no one uses that method?

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The thing about that method is that it doesn’t work.

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I wondered its just a blue berry thing then lol TY

No, it won’t eradicate the mildew at all, no matter the plant species. It’s an old wives tale/broscience.

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dude grows perfect blueberrys LOL but we don’t know all his secrets right :slight_smile: he’s got a very popular channel that would be real risky for him to put bogus recipes out

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Growing Out The Box

Ok what you should do is go out and get a mildew colony and bring it into your grow. Then show me how whey kills it off and we’re talking. What I see on that video is pseudoscience.

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Whooo, 18 million views. Yee freakin haw. That mans got the gift.

This is the strange part. When someone makes the claim that “do this and it will prevent you from getting mildew”, whatever they have to say next is suspect. Unless they say don’t bring in any contaminated material, they don’t know how you start an infestation. So that means they don’t know what they are talking about. It’s really easy to fool people who don’t know how the parasite lives, though.

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I get bud rot haven’t sorted that out yet never seen the mildew others get its hot n dry here and I’m not arguing so dead issue man I get it.

Living on the East Coast has led me to try various methods to eradicate powdery mildew outdoors. I’ve experimented with whole milk, which I read contains enzymes that suppress PM by outcompeting it. I’ve also used potassium bicarbonate, which proved more effective. Hydrogen peroxide diluted with water was another method I tried, but it essentially melted the trichomes but it worked.

I grow indoors during the winter, and this was my first time encountering PM in an indoor grow. I sprayed Zerotol HC during veg, and again at around week 3 during defoliation.

Despite that, I still got PM in flower. I used Zerotol on the 2 plants in mid flower since it doesn’t affect the trichomes or flavor and is safe for use throughout the grow. Out of my two plants, only one developed a small recurrence of PM even after using Zertol .

I have to note that I really didn’t use Zertol as much as in the protocol . I wanted to keep spraying at a minimum . On my outdoor grow I’m about to start I’ll be more proactive in using it regularly.

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So, I tried alcohol and it’s yet to rear its head again, and I did a milk spray just for fun before I left for England, but I’m just not confident enough that those will kill the actual mycelial
colony.

My prilled sulfur was a HUGE pain in the ass to try and grind by hand, so I ordered some
powder and I think I’ll try and sift it before throwing it into a sprayer. The only reason I resorted to non-sulfur methods was because of the grinding and mess from the prills.

15g or so per liter, @JoeCrowe?
Also, would you be able to explain how sulfur is able to address the issue systemically? I’m trying to learn as much as I can. :sweat_smile:

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Here’s how it works. The sulfur mixed with water is like acid to the colony!

If you watch this video I took of me dumping some sulfur powder on the colony and then adding water. Once the sulfur and water mix, it kills the colony quickly. You can see it popping like popcorn.
The colony is on the exterior of the plant, so you just have to spray the shit out of it and the colony disintegrates. You do the spray twice to make sure it’s good and dead. I give it a 50/50 chance of killing it with one spray, so don’t go there. What I noticed when I finished off the colony in my grow is it seemed to crush it instantly, and then I did the second spray 2 weeks later, but I had never seen it come back in the meanwhile. After the second spray I cleaned everything up in the grow room. Washed dusty surfaces, but not because the mildew is there. Keeping things clean is an important aspect of growing.
There is a list of things that will fail to work when you are trying to get rid of the mildew. I’ve tried so many of them, personally. Even bleach failed! So I stick with what I know works. The mildew never came back 20 years later, or more like 25 now. You use a tablespoon per liter, and if you have prills, make sure you grind the hell out of them in a coffee/spice grinder, not used for food.

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Yeah I was using the mortar and pestle that I usually strictly use for medicating fish food, but it was messy as hell. :joy:

I read somewhere that spraying any type of liquid/solution only address the fruiting bodies of the mildew, and not the systemic issue infecting the interior of the plant (mycelial network). Is that just plain untrue? Is mildew an exterior issue only?

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Yep, it only grows on the surface of the plant, but feeds on the plant through the stomata on the leaf.

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And the sulfur penetrates deep enough to destroy the feeding/root area of the organism? Sorry, I’m not very well- educated on the anatomy.

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It’s just a mycelium network made from hypha/hyphae like most fungus. Something like bud mold aka botrytis cinerea has a network like that. Mildew is an obligate biotrophic ascomycete, which means it needs it’s host to live. There are two main forms of reproduction, which is the ascospore(asexual) and the chasmothecia which is sexual. The sexual reproduction has to perennate before it starts a colony.


Just keep in mind this image isn’t mildew from Cannabis. There is no chasmothecia on weed mildew because it reproduces asexually.

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Interesting. Thanks again man!

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Perhaps I should put them under a more powerful light! They are growing, but not very fast.