Has anyone here defeated powdery mildew?

I stand corrected… thanks

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Same here. I used a Petra tools backpack fogger. Haven’t seen that parasite since. Gonna spray my entire garden and my lilac bushes yet this year. Plus again this spring.
I think protocol is like 30 days after an oil based spray to be safe using sulfur.

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One word, Zerotol.

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a

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read this thread some months ago and happened to get pm this year after not seeing the stuff since i returned to growing at home in 2015. Took a few clones and and 30 or 40 days later it started showing up.
I used the sulphur spray as recommended in this thread and have not seen any pm since then and it has been well past the 40 day window.
I did just have to nuke a room to deal with a spider mite outbreak but no pm to be found.
Just thought i would share that

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can you link the spray you used. been battling it last 4 months and its killing my drive…

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I just went to the local garden center and found safer’s sulphur dust. It says it is 92% sulphur.
Have not seen and mildew spots since beginning of november when I did my first of 2 sprays.
It left a lot of residue on the leaves after it dried so 3 days after spraying I sprayed with water and h202 to clean off the sulphur residue. The applications seemed to work for me but I’m not entirely sure the Safer’s sulphur dust was the product recommended by @JoeCrowe . I was just in a panic after not seeing it for many many years and had counted myself lucky to find any kind of sulphur product in my little town in the sticks LOL

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The safers sulfur will fuck it up, and it won’t come back! BAM! That’s what I used on the greenhouse to wipe out the mildew on the cucumbers. 92% is super lethal to mildew!

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I used this one:

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Ive gots the PM
I sprouted seeds when I did I didnt have a space set up. So, hello PM.
But, Im not worried.
I ordered some stuff to kill it, should be here after the weekend.

I’ll post pics in about a month to see if an alternative to sulfur does work.

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Silica, amended into media from the beginning. Wollastonite for soil and peat applications. I use 5g/gallon. Credit to USU.

For DWC people use a soluble silica product; though there are two very different compounds on the market.

For indoor, add engineering controls. Tape or otherwise affix a MERV-13+ filter to an air intake spot on the tent, or extend an intake duct to a homemade filterbox (plastic bin with furnace filter taped to the top, hole drilled in side, sucking air in).

Outdoor, foliar apps of soluble silica product mixed with a dash of kefir (or milk). Milk solids, casein, and silica all coat the leaf tissue again like a clearcoat.

Once we’re talking bio-active agents and chemicals, I figure WPM has won the war, it’s inside the fortress.

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Yep sulfur is a fungicide. 92% sulfur is marketed specifically for it. Do you spray in flower though? Is it more for complete house eradication between seasons, or is good for flowering cannabis, or?

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Joe’s method worked here as well.

I’m very happy with results and no ridiculous price. Not in flower and not following an oil application.

Joe earned a cape.

.02

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Absolutely not in flower you might get away in week 1/2 of flower if it means loosing to the mildew but safe to stick only in veg .

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Yah I go with never spray anything in bloom, but definitely don’t spray your plants with sulfur in bloom. The sulfur will sterilize any plant that has mildew on it and any bits of plant laying around. In that way, it’s perfect for breaking the cycle that mildew relies on to propagate each year. It’s especially expedient in the grow room, taking 2 weeks to complete.
Spray once then two weeks later spray them again, but never in bloom. 1 tablespoon 90%+ sulfur mixed with water. Half that will work, as well. Soak the plants down. Never use within 30 days of an oil application.
Phew I think that covered it all?

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Thank you @JoeCrowe this is really helpful.

I have a squash bed outside, zone 5B, and every year my squash gets hammered with WPM. The zucchinis and cucumbers are able to put up a better fight but also get hit. The eggplant is immune and always has been :man_superhero:. So I test things on the squash for that boss-level difficulty setting.

That silica+kefir stuff I mentioned has been a big help, but it requires very regular maintenance. I was able keep it off the cucs (kooks) and zucs (zooks). The squash went from fully f**ked by mid June, to ~80% healthy by harvest.

Anyways, I’ll be deep diving the sulfur strategy based on your recommendation.

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What I did with the pumpkins is I went into the greenhouse and sprayed all the plants that could get it. Pumpkins, cucumbers, butternuts and all the plants material laying around. It ended the mildew and now I don’t have to spray it again.

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I can attest that Joes suggestion works, and I tried everything before the sulfur…two applications two weeks apart and I haven’t seen powdery mildew in quite a few months…my posts are somewhere up in this thread. It is so fantastic to not have to deal with that shit anymore.

Ps, I vowed to send you some clones once confirmed that it worked, let me know what you want buddy.

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Wow, it’s been so long I had forgotten! I’m glad you could save your gene pool with like a buck’s worth of sulfur. All the “zany” suggestions just drain your will to live!

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Monterey orchard spray is a great product also that contains sulfur and will absolutely rid a garden of the pm plague. I mix it at half the suggested strength and does the trick.

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