This is all pretty interesting, Matty. With the variety you have, have you tied to figure out which plant families support the pm that infects weed? Could be a real hero if you find that out 
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I swear that’s one of the only powdery mildew I can’t find around here. Wow but I have quite a list of plants that it’s NOT!
clover
comfrey
aster
dandelion
squash
plantain
peas
wood aven
columbine
derrr I may have forgotten some. It might be something a person could crowd source by looking at people’s outdoor grows. The thing is… it’s a tricky question to answer if you are looking for a positive you have to get all the plants you suspect to be the host and place them underneath an infected cannabis plant to see if it spreads. In containment.So you need a room and a host plant(or multiple) you suspect as well as an infested cannabis plant. That’ll give you throughput in the test, rather than trying to find infected hosts and get them near a weed plant.
Good news though, rather than an infinite list of plants to test as the host, I can tell you for sure which ones it’s not and eliminate like 8 possibilities! lol! That’s why it’s so easy, yet at the same time a difficult one to pull off.
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We finally have mildew showing up on the target plant! So, either it was there already, or can spread that far. Also not eliminating the fact some…one could have assisted it. Not a falsification, that’s what I can really say!
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I have all of those, except for wood avens. I had to look that up, and almost every pic had pm, lol!
What’s the plant w/pm you’re showing next to the dandelion?
Other plants, besides what you’ve listed that we’ve had with pm
bee balm
zinnia
sunflower.
Never seen it here on comfrey or dandelions.
You’d be the guy, though!
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That’s the red clover, those weeds are growing everywhere around here and they’re just riddled with mildew.
I don’t remember the comfrey having mildew like a decade ago, but also, I wasn’t really looking. I was over at my friends place just wandering around his yard looking at the various wild plants. The wood avens and plantains were infested 20 km away. I think the infestations on the native weeds has been spreading for longer than a human can conceive. For plants that are non-native, the mildew is non existent. Invasive species seem to be everywhere, but the mildew that infests them hasn’t reached the same level.
I’m definitely not ruling out the possibility I could determine another host plant for the cannabis mildew.
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You know, I’ve been thinking about the powdery mildew and the sulfur protocol. I know the mildew can’t survive a brush with the sulfur because it like, disintegrates very quickly on contact.
The thing that’s so surreal is the way it works. 2 sprays and it won’t come back! OR one spray when it’s dormant. Except, it’s not like the spray somehow magically floats and covers the entire mildew colony somehow does it? Or the thing like I know I just spray twice and the mildew is dead by spraying the hosts, but two sprays destroys the colony? Like… so far as my brain can figger ooot is that the entrance of the host plant in the environment triggers the mildew colony and then only the shit that lands on the plant survives and that gets nuked by the sulfur? I’m trying to puzzle out the series of events using logic and observation. Give me something I can test perhaps.
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I see the mildew is starting to re-creep where I had finished it off. It spreads slower than I thought it would, but by the end of the season it will probably have re-taken the 1x1meter I sterilized(plantain mildew). In the garden though, the mildew that was living on the calla lilies is definitely toast. Same with the greenhouse mildew from the squash and cucumbers, it’s dead. They were most likely the same colony!
I have found another host plant! Buttercup! That damned weed hosts mildew colonies as well around here! So many different infected plants, it’s crazy like a dozen different mildew colonies or something. Unreal! I think the sweet peas have it as well.
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ooo interesting colony on the sweet peas! No strange pod things with mycelium going to it. Just annual replicating colony. The mycelium network is quite dense!
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I sprayed one of the sweet peas with sulfur and left the other untreated. I didn’t keep track of which was which though, lol! I will assume the one without mildew is the one I sprayed. Now, this is my question. Which plant is the host for the mildew on the peas?
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these are pumpkins is this pm following the veins of the plant several plants only one showing this. sprayed with sulfur 2 days ago
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Naw, that’s a natural coloration of some squash plants. On the other hand, I see some white-ish crust around the edge of the big leaf there on the right hand side. That looks like mildew. Too late to finish it off though I’m pretty sure it’s in replication mode in late season. I’ve never found a sulfur spray finish it off at that point. What you need to do, to make sure it doesn’t come back next year, is spray the squash/pumpkin plants after you plant them, and then again 2 weeks later. Or you can spray around where you grew them before planting.
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thank you for the quick reply Joe always next year is what they say i mean what else can you say
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Keep an eye on it, if you do the two sprays you might be able to get rid of it. At minimum you can keep it at bay for 20 days!
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Joe - any need for a surfactant when you spray sulpher ?
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Only for hydrophobic plants that really shed water. I don’t use a surfactant when I’m spraying cannabis or squash plants.
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Thanks bro. Also, how long does it need to be on outdoors before rain arrives ?
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Honestly I don’t think it washes off after it’s dried on there. Like rain won’t hurt it.
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Joe - I thought of another question - can it applied outdoors under the sun or is spraying at dawn or dusk better ?
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I spray during the day, and it doesn’t really matter. I sprayed in the greenhouse and outdoors during the summer in the daytime. noon or 1pm heh heh. The critical part is not to mix an oil based substance with the sulfur spray, or else the plant will get holes in it.
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I have a story!! So I told this guy to spray some sulfur on your plants to get rid of the mildew. He told me sulfur was a toxic heavy metal. The fucking disbelief was evident on my face. Then he says well, I don’t really know. Then claims the sulfur is systemic and will test positive in the lab. More disbelief! lol! I was like whaaaaaa? I think he was thinking of that poison. Meh. Well he proved at least, that he doesn’t understand chemistry. In my minds eye, I can see the periodic table. Sulfur is over in the non-metal category where it bonds to itself. S2, elemental sulfur.
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