Hydrogen Peroxide (H2O2) Bath and Powdery Mildew

phrygian44

Well-Known Member
OK, so i did something really stupid last week. Powdery mildew was all over my leaves and staring me right in the face, and for some reason it just didn't register. Like, seriously, WTF was wrong with me. I've been gardening for many a year and have seen powerdry mildew on my roses and other plants, but this is my first cannabis plant, so for some reason i just didn't make the connection. :wall:

and since the weather was going to be reasonably warm for another two weeks, although rainy, i decided to push the harvest. When i finally chopped her yesterday, the mildew had taken over and destroyed about 20% of the buds (grey, powdery mold), with the rest of them looking OK, but dreadfully limp and unhealthy. :cry::cry::cry:

I friken panicked - it was a sizable yield, with the plant being perfectly healthy just the week before. i therefore searched this forum and the Googlatron and everyone was recommending giving the plant an H2O2 bath. I was so leery to try this, at it sounded like such a drastic measure, and i didn't want to loose all those trichomes that I've been cultivating and talking to every morning (lol), but I'm very happy to report that this trick is a life-saver and saved the harvest. :D :weed:

So for those of you that are leery about having to do this, or don't know what to do, don't worry, it works out without any problems and is very easy to do. Here's the scoop:
- you will need to fill the bathtub up high enough with a mixture of water and H2O2 to be able to submerse your stems/buds
- the general consensus for the ratio of H2O2 to water is 1 cup Hydrogen Peroxide (@ 3% volume) to 1 Gallon (80 Cups ) of water. now, since i was in panic mode, I pushed the ratio to 1.75 cups H2O2 to 1 gallon. of water (more on this at the very end)
- gently put the stems in the bathtub and push them under the water. keep doing this to get all the air out of the buds so that they stay under the water.
- set a timer for 5 minutes.
- gently agitate (key word being "gently") the stems to get flow into and around the buds. i grab a stem from the bottom and move it back and forth (left and right) inside the tub, very slowly. continue and repeat with all stems until the timer goes off.
- when the timer is up, i just hung them up on the soap rack pole to drip-dry for about 5 minutes so that they won't drip all over the floor when carrying them to your proper drying location. Note: you do not have to rinse them, as H2O2 is just water with an extra oxygen atom attached, which will dissipate naturally into the air on its own and not stay on your plant. you also want this oxidization process to occur as it's also part of the mold killing process.

Side, Side note: if you have gum desiese or problems, put a mouthful of H2O2 in your mouth, swish it around for a few seconds, and then open you mouth and keep it open to let the air oxidize the O2 (1-2 minutes). you mouth will foam and tingle. that's the oxidization process working, and killing the infection in your mouth. no more bleeding or infected gums if you do this about once a week. Brush your teeth when done. CAUTION: DO NOT SWALLOW​

- after the stems are dry enough to not drip all over your house, move them to your basement or drying area.
- set the fan on high and directly onto the hanging stems. you want maximum drying power at this stage to dry all the water as quickly as possible
- after about 15-20 min. either turn the fan around so it blasts their back side, or simply turn the hanging buds around so that their other side is now facing the fan.
- check after another 20 minutes, and if the buds are dry (no longer water logged), then you're done and can proceed with your regular drying regime.

Results:
when i checked the buds again this morning with my 30X jewelers loupe, there was no sign of rot or mildew (YAY!!!), and i was absolutely impressed that there was very minimal loss or damage to the trichomes. As far as i could tell, the trichomes were almost as perfect and abundant as before the bath. (Phew!)

Ratio Addendum:
if you're worried about using a too much H2O2 or too strong of a solution, don't. i had one choice bud sitting on my dresser from yesterday's harvest, that looked to not be effected by the mildew, so i just let it sit there to see if if would develop any sign (now that it was away from the rest of the infected plant). Sure enough, the mildew was starting to take over the bud this morning. therefore, as a test, and as per comments on the net that H2O2 does not dissolve or dilute the thrichomes, i decided to put this statement to the test.

I therefore dumped the one bud in pure H2O2 (@3%) for 5 minutes, pulled it out of the cup and let it air dry for a couple of minutes to get some oxidization action going, and then gently rinsed it under the tap. I then held it in front of a fan to dry it.

I'm therefore happy to report that the bud is looking perfectly healthy without any signs of rot, and there was absoulte minimum degradation or damage to the trichomes when looking under the jewelers loupe, before, and after. Yes, there was probably some loss, but nothing really noticeable or to panic about.

I only wish that i had taken pictures of the whole process for everyone's benefit, including what the milew looked like on the leaves, as well as the bathing process, but as i said, i was in total panic and just toke action without thinking about recording it.
 
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xtsho

Well-Known Member
Obviously this can only work for small plants. Why not spray it on?
I cut my stuff up and dry it on trays. I only wash outdoor plants anyway. Indoor I just cut trim and hang. That's the good thing about indoor grown. You don't have to wash all the crap off of it if you've kept it nice and clean. Outdoors I alway seem to find buds covered in bird shit. I cut those off and chuck them. Ain't no washing that off.

My outdoor plants were covered in pine needles and other stuff. Next year I'm screening my outdoor plants to keep crap off and also to prevent moths from laying eggs.
 

hotrodharley

Well-Known Member
I cut my stuff up and dry it on trays. I only wash outdoor plants anyway. Indoor I just cut trim and hang. That's the good thing about indoor grown. You don't have to wash all the crap off of it if you've kept it nice and clean. Outdoors I alway seem to find buds covered in bird shit. I cut those off and chuck them. Ain't no washing that off.

My outdoor plants were covered in pine needles and other stuff. Next year I'm screening my outdoor plants to keep crap off and also to prevent moths from laying eggs.
I was under the impression from the original post this was done to a living plant. My mistake.
 

phrygian44

Well-Known Member
... Why not spray it on?
was thinking about it already for nex year if i come across this problem again (now that i know that it doesn't do any damage to the trichomes), and therefore i can extend the harvest, as i wanted to end up doing this year but I panicked.
 
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phrygian44

Well-Known Member
I only wash outdoor plants anyway. Indoor I just cut trim and hang. That's the good thing about indoor grown. You don't have to wash all the crap off of it if you've kept it nice and clean.
i cut the plant down into its main branches and then hang dry them. that's why i used the bathtub approach, as i didn't want to have to deal with so many smaller sections. 10-15 branches is much easier to deal with than 50-60 smaller sections.

yeah, indoor would never require any bathing or washing, unless you have some really bad fungus floating around da house and it's getting into your tent. :shock:
 

xtsho

Well-Known Member
i cut the plant down into its main branches and then hang dry them. that's why i used the bathtub approach, as i didn't want to have to deal with so many smaller sections. 10-15 branches is much easier to deal with than 50-60 smaller sections.

yeah, indoor would never require any bathing or washing, unless you have some really bad fungus floating around da house and it's getting into your tent. :shock:
Same process just larger container. I only had a few smaller plants so I just cut it up and washed in one bucket, rinsed in another. Then spun in a salad spinner and laid it out on a screen with a fan blowing to dry off all external moisture. Then onto drying racks.

My outdoor was cut before it was ready but that was due to mother nature. It will be used for dry ice hash that will be pressed into neat shapes and given as christmas presents. I've started the indoor which is what I use for my personal stash.
 

ComputerSaysNo

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...).
 

phrygian44

Well-Known Member
Then sprayed the plant with diluted milk (1:9). Will repeat tomorrow.
Would use potassium bicarbonate,).
Interesting. both remedies are rated highly effective for eliminating PM.
Thnx. I will include these in my arsenal for Cannabis.
I always use Neem Oil or Sulphur products on my plants, but then again, i don't smoke those plants, so it was never a concern what i used.
 

ComputerSaysNo

Well-Known Member
I used potassium bicarbonate bath then H2o2 and then a water rinse to clean my outdoor
I don't see how doing this in three stages is better.

I'd rather prepare a dilution of H2O2 and potassium bicarbonate (in the same bin), rinse the flowers in there, then just dry and consume.

Rinsing with water is not going to be beneficial in my opinion. The H2O2 will completely dissolve, and the potassium bicarbonate should not leave any traces as well.

If you rinse it off straight after, you might as well do without the potassium bicarbonate.

I will probably simply use baking soda this time (if at all). H2O2 alone is probably sufficient already.
 
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