Has anyone here defeated powdery mildew?

Im 69, been making hash since high school, lol.

Id ask you your method, IF…IF…IF you condense it into 5 full readable sentences

Deal???

:sunglasses:

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four steps:

  1. get the ultimate pheno hunted plant using elimination trials
  2. make freeze dried hash
  3. win the contest
  4. rip the hash?

The first two steps are the ones that have finer details!

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I won’t make hash any other way but freeze dried since trying it . It rules over any other way I’ve made it .

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ill just paste this here for general FYI

Different methods to control Powdery Mildew (PM) (video by a chemist and horticultre PhD)

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Like the test I did with Ozone.

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Interesting video. I’ve found that the giant knotweed extract, as described in the video, to be effective. Though, my experience has been anecdotal as I wasn’t running any controls while in use. Once source of giant knotweed extract can be had from Marrone Bio-innovations under the name Regalia.

Also, interesting are the results of using mono-potassium phosphate, other potassium phosphates, and even potassium nitrate foliar. Easy to source and relatively inexpensive. The studies claim ~10x reduction of spore germination over the evaluated timeframes for their trial crops. FWIW, the bud buster foliar spray (sponsor) is ~20% potassium phosphate. Some folk here have been applying it, they may have some experience to share in regards to PM.

What would be particularly interesting is understanding the mechanism of suppression for each of these. If the mechanisms differ, for instance between RE and MKP, would a combination of the two provide even greater protection?

Also, when I’ve experienced PM … usually localized to a fan leaf or two, it has been during flower. I do not recall seeing it during veg. That is for runs that are running seasonally in that during flower it’s also typically cooler with perhaps at higher relative humidity (late summer/fall weather). At the same time, the nutrient needs of the plant have shifted. Further, do the calcium, silica, and potassium ratios prior to flower have a long term effect on the susceptibility of a plant to cell well intrusion by the germination hyphae, et al.

Attached here are the referenced papers from the shared video:

Effect of certain plant extracts and fungicides_abdu-allah2017.pdf (1.1 MB)
EFFECT OF VEGETABLE AND MINERAL OILS ON THE DEVELOPMENT_04-25.pdf (696.1 KB)
Induction of defence-related_moharam2013.pdf (402.5 KB)
Suppression of cucumber powdery mildew_reuveni1995.pdf (453.3 KB)
Integrated disease management of_sudha2009.pdf (1.4 MB)

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Oh in case anyone missed it, this is the gazorpazorp thread, I’ve moved the education to the lab. That’s where you’ll find me. This thread is where “the boys get the play outside”!

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:cowboy_hat_face:Many fungicides are available—look for one containing potassium bicarbonate, neem oil, sulfur, or copper. You can also create home remedies—one made from baking soda and one made from milk—that can help to prevent powdery mildew before it starts.
For continuous protection, reapply fungicides every seven to 14 days and be sure to follow the label instructions for both application and the waiting period before harvesting fruits and vegetables. While fungicides won’t cure powdery mildew, it can help stem the spread of the fungi to other leaves or plants. :mage:

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First referenced paper “Effect of certain plant extracts and fungicides” is pure gold, but the rest… uhh… questionable at best.

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I combine neem oil and potassium bicarbonate as a simple and effective all round pesticide for use in veg after reading a paper about how carrier oils increase the effectiveness of potassium bicarbonate. Simple and effective but like you said there are as many ways to handle PM as there are growers out there.

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You should reach out to the the paper authors to let them know.

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Not much hope there. Bugbee even ignored the memo I sent him.

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7 posts were merged into an existing topic: Powdery mildew - An easily exterminated parasite

We are getting a pretty healthy PM outbreak here. White spots are mainly showing up on the leaves. Another thorough inspection needs to happen for infection in the buds. Should the plants just be chopped even though large sections are still white pistils and clear trichomes?

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How early are they you think?

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The simplest and most effective DIY pm treatment I have found that actually works is: Accuratly measured In 1 Gallon of water, 1 table spoon of baking soda, 1 tables spoon of veg oil (can be replaced with any oil, neem, ect.) And half a teaspoon of organic dish soap. If you follow those measurements. It is a very good pm treatment and preventative. Shake well before use.

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Probably would want to let the flowers go another couple of weeks. Some colas have red pistils at the tops, and are not ready as you go down the stem. And others the entire colas are still full white pistils.

For sections with PM, was considering chopping and freezing for ice water bubble hash or for edibles.

These buds are likely all going for hash storage (pre-edibles) or straight into butter. If there are non-toxic sprays, open to suggestions as maybe the ice-water hash would separate that out.

Can that be sprayed on whole plant, including fairly developed buds?

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I would avoid directly spraying the actual buds. But I’m sure you could if you did a bud wash at harvest. But still you should avoid it. This is generally for veg and as a preventative before flower. Use this during veg, then you can continue a treatment of water at a high ph like 9+. This should prevent the pm spores from being able to reproduce and grow on the leaves and stems. The goal is to make an environment on the leaves and stems that the PM spores can’t land on and grow. Using a high ph I found is one of the best options after your plant is infected. (in a DIY situation.) I have tried using an acidic solution to keep pm at bay but that kind of stressed the leaves for some reason. So I went back to a high ph. You can also buy products that advertise being able to spray flowering cannabis. I hear Dr. Zymes can be sprayed on flower but I have never used it and don’t have any personal experience. Just the word of mouth. So I would recommend doing some research before using it.

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There’s ways to delay/mitigate the spread like spraying with high pH water, using UVC light or hydrogen peroxide but those have to be done pretty much daily/every other day to really do much. Some organic growers swear by spraying with milk as there’s some research to suggest that in strong sun the milk breaks down and creates an antifungal, others swear by LAB’s. The first three I’ve used in indoors grows to control PM until harvest when a thorough cleaning can be done, the last two I don’t have much experience with and wouldn’t form an opinion as LAB’s didn’t seem too effective for me and my only experience with using milk was on dry farmed plants that I barely checked up on (although the PM didn’t get out of control, whether that was the milk or change in weather is a guess though).

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