Hydrogen Peroxide (H2O2) Bath and Powdery Mildew

ComputerSaysNo

Well-Known Member
both remedies are rated highly effective for eliminating PM.
I sure hope the milk will work. It was not an extreme infestation at this point, but it had proliferated to pretty much the entire plant. There has been a few cool, damp days, and that was probably enough.

The plant has only quite a short while to go, so I don't know if the milk will even be effective. If I won't see any more signs of PM at harvest, I will record that under "success".

I've seen very local PM infections on that plant during late summer, but never anything serious.

I will definitely point the H2O2 cannon at the buds before drying them, as you did, because I'm fully aware that the mold can spread in no time while drying.
 

EhCndGrower

Well-Known Member
I have had terrible luck with wpm on my outdoor grows. I used the milk treatment and the h2o2 treatment when outside and one harvest in a h2o2 bath. I have lost a ton of buds to rot and everything was covered in wpm, but I find the baking soda, lemon juice and water worked better. I thought the buds looked overall cleaner and buds seemed to taste better as well. Just had some of my American Pie and the smoke seemed smoother then the Mango Sapphire that got the h2o2 wash (both followed by 2 more buckets of water) I should also mention I harvest/wet trim everything down into buds so I can throw them into my freeze dryer and dried/cured the next day
 

ComputerSaysNo

Well-Known Member
I have lost a ton of buds to rot and everything was covered in wpm, but I find the baking soda, lemon juice and water worked better. I thought the buds looked overall cleaner and buds seemed to taste better as well.
So what did you do exactly? During the grow and after harvest.
 

EhCndGrower

Well-Known Member
So what did you do exactly? During the grow and after harvest.
I would spray my plant with water/h2o2 or water/milk to help keep the wpm to a minimum every 3-4 days. It never got rid of it but for sure kept them at bay enough to harvest a chunk of the plants. Then at harvest I cut my plants into buds, wash them in the above milk/h2o2 combo in one bucket, 2nd bucket of water near room temp and a 3rd bucket with just slightly cooler water then that one. I then put them in a salad spinner to whisk away the excess moisture, place on drying trays and into my freeze dryer for now about 28hrs to dry/cure
 

Skunkbudz

Well-Known Member
has anyone else tried an H2O2 bath for other infestations, other than powdery mildew?
Yes cleaning a very small outside harvest < 2 lb. Lots of airborne shit little Flys bird shit , seemed to workout but took some extra time. I was shocked that the buds didn't soak up any of the water but seed a video and tried it.
 

JimmiP

Well-Known Member
I've found PM on a lot of the leaves of my outdoor plant today.

Cut most of the leaves, the plant is due in 10-15 days anyways.
Then sprayed the plant with diluted milk (1:9). Will repeat tomorrow.

Will definitely wash the harvest in H2O2, and probably add baking soda to the dilution as well (it is supposed to inhibit the mold spreading while the buds are drying). Would use potassium bicarbonate, but it's more difficult to acquire than baking soda (obviously...).
Amazon...Screenshot_20211015-200704_Chrome.jpg
Pretty handy stuff to keep around.
 

ComputerSaysNo

Well-Known Member
Will definitely wash the harvest in H2O2, and probably add baking soda to the dilution as well
Quoting myself. Don't add baking soda to the dilution, it will only decompose the H2O2.
My plan is to simply bath and rinse in 1% H2O2, then dry under fans, then continue to dry normally. No multi-step washing, I don't see the benefit. The H2O2 will do its thing and just decompose and/or dry off.
 

ComputerSaysNo

Well-Known Member
Amazon...
Pretty handy stuff to keep around.
Yeah, I've found it too, but it's probably not necessary to keep around for this purpose. The milk dilution is supposed to work really well to keep PM in check on living plants, and bathing the crop after harvest in H2O2 is probably enough.

There are several published results on using milk (at 40/60 milk/water ratio) as a spray, and the results are convincing. Apparently it works just as well as commercial fungicides. There's a smell, but it dissolves rather quickly.
 

JimmiP

Well-Known Member
Yeah, I've found it too, but it's probably not necessary to keep around for this purpose. The milk dilution is supposed to work really well to keep PM in check on living plants, and bathing the crop after harvest in H2O2 is probably enough.

There are several published results on using milk (at 40/60 milk/water ratio) as a spray, and the results are convincing. Apparently it works just as well as commercial fungicides. There's a smell, but it dissolves rather quickly.
I use it quite a bit (in a spray) as a preventative measure. And then again in my first wash bin.
 

phrygian44

Well-Known Member
The more I read, the more growing outdoors sounds like a nightmare. I don't know how you all deal with the anxiety.
my plant was perfectly healthy all year, and reached almost 8' tall (you ain't gonna achieve that in no tent), with no anxiety up until the very last week before planned harvest when PM hit. i was then taken completely off-guard as i had no idea what to do.

now that I'm all the wiser, I plan on growing 8 more next year outdoors (4 here and 4 at my dad's place). the cost of the tent and lighting and misc. equipment and setting up and maintenance and fans and constant monitoring and watering and feeding and air filters and electricity bills can be just as daunting (where outdoors I just planted it once and watched it grow, with some additional feeding during the bloom phase), so each method has its advantages and disadvantages.
 

lusidghost

Well-Known Member
my plant was perfectly healthy all year, and reached almost 8' tall (you ain't gonna achieve that in no tent), with no anxiety up until the very last week before planned harvest when PM hit. i was then taken completely off-guard as i had no idea what to do.

now that I'm all the wiser, I plan on growing 8 more next year outdoors (4 here and 4 at my dad's place). the cost of the tent and lighting and misc. equipment and setting up and maintenance and fans and constant monitoring and watering and feeding and air filters and electricity bills can be just as daunting (where outdoors I just planted it once and watched it grow, with some additional feeding during the bloom phase), so each method has its benifits.
I just keep reading about bugs, molds, thieves, crazy neighbors, unpredictable weather and whatever else. It seems so scary out there.
 

phrygian44

Well-Known Member
I just keep reading about bugs, molds, thieves, crazy neighbors, unpredictable weather and whatever else. It seems so scary out there.
I hear ya. I thought I was going to have all those problems too, but the plant was amazingly bug resistant all year (probably because of its defensive odor), and the neighbors are all doing the same (lol).

Biggest problem is the lenght of the growing season depending on you strain. My plant was 21 weeks in and still could've used another week or two, but the growing season where I live is at around 20, before it starts getting cold at night (4-5C), and the Fall damp and rainy weather comes round. That's when i started having any problems.
 

Treesomewanted77

Well-Known Member
The potassium bicarbonate is also sold as green cure and works wonders on WPM and can also be used in a wash before the dry. I normally use 1-cup lemon juice & 1-cup baking soda to 5 gal of water as my first wash then I rinse then into a 5 gal wash with potassium bicarbonate then straight water rinse again then hang. It’s best to have the first 2 washes be Luke warm so the tricomes don’t get to cold and fall off and the straight water rinse to be just cool tap water and I don’t loose many tricomes at all unless I really mash them around in the washes. I even wash my indoor because I have 2 dogs and hairs get everywhere so I prefer to wash them all. Yes lusidghost outdoor can be a big PIA and at the end you may not end up with much reward but if you make a good plan and work your plan it can be very rewarding. I built a 10x20 hoop house just because I live in a very humid part of the world so it helps keep a lot of the moisture off the plants. Next season I’m going to try light depervation so I can be done before the rain season kicks in.
 

ComputerSaysNo

Well-Known Member
we talkin' skim, 1%, 2%, 3.5%, homogenized, pasteurized, non-pasteurized, buttermilk, kiefer, organic, grass-fed, goat, low-fat, soy?
com'on, man, stop keeping us in suspense.
Serious answer: this probably does not matter, because it's about the whey, and not the fat in the milk. Probably one can simply use whey powder dissolved in tap water. In one of the articles I've found they've used milk powder for the study.

Apparently it's important to spray while the sun is shining on the plant, because the sun light seems to play a role in breaking down the milk proteins for the antiseptic effect. How it works exactly is not fully understood.

Biggest problem is the lenght of the growing season depending on you strain. My plant was 21 weeks in and still could've used another week or two, but the growing season where I live is at around 20, before it starts getting cold at night (4-5C), and the Fall damp and rainy weather comes round. That's when i started having any problems.
It's the same around here. The plant itself is secure and hidden, also not much rain gets to it, but right now we get this damp weather, with mild and sunny days in between, and that seemed to give the PM a nice breeding ground.

It wasn't very serious, I could remove the affected leaves, and right now I see no signs of re-emergence. Powdery mildew is one of the most common plant diseases; I guess one just has to deal with it and grow resistant strains.

I'm glad that I can probably pull the plant in around 10 days. The weekly forecast looks pretty good, definitely no frost and not a lot of rain.

I normally use 1-cup lemon juice & 1-cup baking soda to 5 gal of water as my first wash
That does not look right, because the lemon juice (acidic) and the baking soda (alkaline) will mostly cancel each other. You need either an alkaline or acidic solution to work against the mold.

Also, if you wash it all off right away will there even be a significant effect?

It's probably best to just use H2O2 or potassium bicarbonate and then just hang them to dry like that.
 

phrygian44

Well-Known Member
Serious answer: because it's about the whey,
Phrygian44 checks the computer: "Does ComputerSaysNo have a sense of humor?"
...
...
Computer says "No"
:-D :-D :-D

I know it's the whey, but was hopin' to get a "Laugh", or maybe even just a simple "Like". :roll:
Though crowd, you Brits. :-D

PS i only use whey powder on myself, as i firmly believe that if i keep eating enough of this stuff that one day i will eventually look like this.
abs.jpg

It wasn't very serious, I could remove the affected leaves, and right now I see no signs of re-emergence. Powdery mildew is one of the most common plant diseases;
I just wasn't prepared; kinda took me by surprise, so now that i know what to expect, i should be able to better manage this next year.
Thnx for all the advise. <two thumbs up>
 
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