Powdery mildew - An easily exterminated parasite

I gave Kris a hash sample after the chat about mildew. She’s a big fan of mine! Sniff sniff sniffing that lovely hash :wink:
She really appreciated the talk about the parasite, too. Told me to stop by any time I wanted. I gave her a light elbow to the arm and told her it’s the kind of talk that pisses people off, on the internet. We shared a laugh!

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I saw a glowing spot or two on the calla lilies. I was like hmm it doesn’t look like mildew, but I better check.


yah, it’s still clean, I did a really good job on those fuckers. I wonder about the half-ass lilies? Where I just sprayed them once with 1/2 strength. I wonder if there is any mildew on those? I’ll check eventually. It’s hash time, though :smiley: Good days work on the in situ.

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Oh snap! During the nature hike, I was looking at the asters. Here’s what I have noticed about the aster colony. I can find it, but only within a proximity to the garden. Now, that doesn’t make much sense. Except…
I was secretly wondering if the garden was the epicenter of the infestation. I’m going to have to take more samples. What I found out in the world wasn’t mildew.


Just some kind of debris. Even 30 meters away I can’t find the mildew growing on asters.

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ohhhhsnap! Cladosporium! This is part of the plant pathology hunt where I go further afield and look for mildew. I start at the garden, and branch out from there. Once I stop seeing mildew for sure, I take samples and trot them back for analysis.
If I’m not identifying the fungus in question, I’m not generating data. No data means I suuuuuck! lol!

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This is perhaps the craziest shit yet. Found some of that common mildew I see around, growing on yellow hawkweed along with cladosporium.


I keep thinking back to all the plants that were purchased, and then had mildew. Things like the gerbera daisy. Petunias. Dahlia. Calla lilies. Each colony a potential infectious hazard. The mildew on the red clover, and the comfry mildew are everywhere in the neighborhood. Wild aster mildew, not so much. 30 meters away I’m having real trouble finding anything.
I’m hatching a theory. Seems like, the mildew is spread around by human activity? I’m not talking about mildew that’s spreading from plant to plant by itself. I’m talking about the bulk transfer of the colonies from where it was living on non-indigenous plants, and then transferred in on plant material, to start it’s spread from there. Crawling around looking for shit, that’s me!

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DAMN!! Blew my own fucking mind. Holy shit. Nobody will believe this shit, that’s for sure. This story will be legend at pissing people off.
I had that theory about the spread a couple days ago and how the aster mildew was linked to the greenhouse. So… GET OUT THERE AND LOOK! Fuck me! Crawling around. Stopping and looking. Taking samples.
What I saw was this: There is a HARD line outdoors where the aster mildew has spread. I was so shocked, and amazed! I have to…do a deeper dive it’s so ragical. I WISH I knew when the infestation started. then I could see how fast it spread.
SO!!! Get on your thinking cap, human being! Draw a map. Place the pins. Connect the fucking dots!!! Holy shit I’m pumped up about this data, it’s a golden opportunity. IT REALLY seems to be limited by geography layout. Like, it can’t seem to jump these large gaps between hosts. I can almost taste…it…

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Here’s the mildew map for the asters. Mildew was ONLY detected in those red areas.

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There were plenty of host plants by the chicken coop and some up by the shop. All tested negative. Limited spread to the wild asters outside the garden as well. Definitely still confined to an area you can see. I wonder where it started from, right? The host plants aren’t in some concentric circles around anything, but I can put a stick in the ground and start measuring from objects. See if I can locate the epicenter. hah hah all data currently points towards the greenhouse/garden as the culprit.

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That’s putting your reputation where your neighbors are at. :joy:,:clap::+1::+1:

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lol! I roll balls out with future predictions like that. If my observations about the spread are true, it can only be physically carried over from Kris’ to PJs. When I told you it was 10 years and the mildew hadn’t jumped the gap… it has actually been an additional 4 years since I had determined the distance. I just keep stacking on the years. It’s like the mildew on the cannabis. I got rid of it 20 years ago and it never came back. Except that was like 5 years ago I started saying that, lol! So it’s more like 25 years.

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Actually, it’s even crazier than that. I can tell you exactly where in the garden to plant a pumpkin plant and have it grow mildew free. I also know exactly where to plant a pumpkin plant and have it infested with mildew. That’s how much I know about the parasite that infests squash. I’m like it’s best pal.

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How’s this for a future prediction. My brain tells me the evidence will support the idea of eradicating the mildew on the asters by getting rid of the plants. First, I’ll kill off all the plants on the edge of the infestation. And start moving inwards. Since it’s been spreading for more than three years and only made it that far, the spread is limited in scope. Because I know where the center of the infection is located, due to some incredible sleuthing, I’ll move all infectious material there. I’ll also gather the plant next to it with no mildew as long as it’s within 6 meters. We’ll see if I can stick to that rule. I’m swamping myself with fungus biohazard in the lab. Fucking pulsing with it. Each one a moldy sample in a plastic bag. JOY!!!

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wow I got some empirical data, and it’s fucking weird! I got my 60 meter measuring tape out and measured the distance from the garden to the furthest colony of aster mildew. 8 meters. Then I started measuring the distance from infested asters, to non-infested asters. 1 meter was the shortest distance, but most were 2 meters. That fits in the .5 to 6 meter spread. It’s had at LEAST 3 years to make that distance. I’m not saying the mildew won’t make it over the 1 meter distance, just that it hasn’t yet. So… 8 meters in 3 years… so if that were true, the natural spread rate seems to be 3 meters a year in a natural environment. I wonder if that spread is tied to the spread of the plant that hosts it? lol! Each answer, poses 2 more questions.
Wait… you wanna see the receipts??? :slight_smile:


On the Left, it looks like this:

But on the right hand side it looks like this:

Those are just water drops… source? Trust me bro. lol! just kidding I scan it with the microscope to check.

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oh my! Now I know why those wild asters are invasive. Rhizomes! Perennial! tough as nails! I pulled all the plants I could find outside the fence. At least, that should halt the spread, for now.

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So, I’ve got a rage inducing story for ya. Seeing as how mildew is host specific, there is a funny ass way to kill it off.
You stop growing the host plant.
As long as the mildew won’t infest native/invasive plants around your garden that acts as a disease reservoir, the mildew colony WILL DIE. It simply can’t survive, without the host. I used that method to kill off the dahlia mildew, and it was really effective. I could do that kind of shit right now with the squash mildew. If I stopped growing in the area that’s infested and just left it with no host plants for a 2 year period, it should be dead. With the dahlias it was like 5 years between tossing out the host and then planting new plants in the same location.
Old tyme stories put the length at 2 years. I never actually TESTED if you just had to leave it 2 years, but I know that method works.

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Holy! Do I have stories or what?!? There was a crazy storm and the power went out.


Good time to hit the road looking for mildew colonies. I drove to the USA border and stopped in a random location. Started hunting around and before I knew it I could see some wild aster mildew! aha! 5 Km away from my place, I found some, just randomly by the road. Great news then! I’m not solely responsible for it’s spread. You always wonder what it originated from, but there are no answers.
It’s not everywhere, but it’s definitely near human activity. I’m going to have to start hunting deep in the forest. Perhaps there are some threads to follow!

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It’s hard to see through vinegar. But the blob it forms, actually magnifies the image. Fucking bizarre! hah hah acetic acid lens for the microscope.

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Wow! Takes forever for cleaning vinegar to evaporate. You could fall asleep to that video!

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“You stop growing the host plant.
As long as the mildew won’t infest native/invasive plants around your garden that acts as a disease reservoir, the mildew colony WILL DIE.”

Don’t take that part for granted!
I was very liberal with the sulphur this season, unfortunately I didn’t take care of the immediate areas of flora around all my plants.
So it’s rearing it’s head here and there. Definitely won’t do that again!

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Which plants it the colony infesting?

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