Dr. Who
Well-Known Member
You over used it!
Will spraying h2o2 on buds negatively effect the buds or degrade the thc?
- Thread starter thatreedocta
- Start date
Hey dr who, I’m about a week from harvest on my last 2 clones and I’ve had Pm on a good amount of my plants that I just harvested. I sprayed with baking soda, water and a touch of organic soap and it stopped the spread for a couple weeks, but it made the pistils turn dark brown. I just got a tub of green cure in the mail, do you recommend using it 1-2 weeks from harvest and at what dosage would you use it? I have done a bud wash on all the plants and cut off any leaves with PM. I don’t want to alter the taste of the buds but you seem to have good experience with it
Renfro
Well-Known Member
Just sulfur vape the room and gear. Done, problem solved, PM won't come back.
Dr. Who
Well-Known Member
I would use it at 1 TBL per gallon of water.. More then that or daily repeated use will brown those pistils out....
You can wash your buds of PM - old Jorge trick. he has a video for that too.
Google up Jorge Cervantes - H2o2 wash buds or washing buds of PM...
I would use peroxide I had powder mildew when I first started and all I used on my plants was milk and peroxide i would spray my whole room down with the peroxide and I never seen powder mildew again after that harvest I was actually told at a grow shop to spray my plants with peroxide right before I hang them up to dry and ive been spraying my plants with peroxide for 4 years now at least once a week for preventative measures and never once had a problem
randallb
Well-Known Member
PM is an absolute suck!
To knock it back enough to harvest I use two quart sprayers. In the first bottle is 1 quart water , 1/4 teaspoon baking soda and 1/4 teaspoon diatomaceous earth. In the second quart bottle is 4 teaspoons peroxide and the quart of water. Spray the plant down w/first bottle, including stem and leaf undersides. Then let sit for 5-10 minutes and blast it with the peroxide mix. It will knock it back, but it can dry out the sugar leaves bad, buds are ok. In fact, the bud will get further washed in H202 prior to hanging. The bud and hairs looks normal when done. I compost all the trim/leaves etc I would normally make hash from, those are nasty. Doesn't solve the problem, but it will get you home. The more expensive options out there don't really work any better in my exp.
To knock it back enough to harvest I use two quart sprayers. In the first bottle is 1 quart water , 1/4 teaspoon baking soda and 1/4 teaspoon diatomaceous earth. In the second quart bottle is 4 teaspoons peroxide and the quart of water. Spray the plant down w/first bottle, including stem and leaf undersides. Then let sit for 5-10 minutes and blast it with the peroxide mix. It will knock it back, but it can dry out the sugar leaves bad, buds are ok. In fact, the bud will get further washed in H202 prior to hanging. The bud and hairs looks normal when done. I compost all the trim/leaves etc I would normally make hash from, those are nasty. Doesn't solve the problem, but it will get you home. The more expensive options out there don't really work any better in my exp.
Darknes01
Well-Known Member
quick question, what dosage of h2o2 do u use? im in 3rd week of flower and just noticed pm on a few places here and there, i try to cut them out and get rid of them but would like to spray all of them down as to prevent the spread.
Currently trying to increase the room temp above 85 and lower RH to 35-40
matakumbaPro
Member
Many seem to be experimenting, but none has shared the advancements 
Any new experience on the topic, perhaps? If not, I'll try chime in some knowledge, once I obtain it
Seeing that no one is reporting ill effects when spraying H202 on plants in flower, I'll try that as well and learn by experience (again) :S
Any new experience on the topic, perhaps? If not, I'll try chime in some knowledge, once I obtain it
Seeing that no one is reporting ill effects when spraying H202 on plants in flower, I'll try that as well and learn by experience (again) :S
green_machine_two9er
Well-Known Member
I wouldn’t spray directly on the plants. But I’m the subject I did a peroxide wash on outdoor last year. We passed state compliance tests even on the dreaded “yeast” which supposedly can’t be controlled outside I was told. But yeah seems like the peroxide bath was beneficial.
2 qrt 3% per 50 gallons of warm water. Followed by two just water rinses.
2 qrt 3% per 50 gallons of warm water. Followed by two just water rinses.
matakumbaPro
Member
I have used h2o2 before, I washed/bathed the buds/flowers and noticed no ill effects when i did.
I tried various solutions from 1:10 to 1:2 solutions, eg. 1:4 would be 1 cup h2o2 : 4 cup water.
I noticed no difference when the concentration of h2o2 were low/high as it always did the trick and I had no issues with the flower afterward (drying, curing etc.)
But this time I'm trying something new... I noticed few light gray fuzzies and I've mixed 1:3 (100ml h2o2 and 300ml plain water) and sprayed while in super late bloom :=)
Like usually, I yolo in the name of science.
I tried various solutions from 1:10 to 1:2 solutions, eg. 1:4 would be 1 cup h2o2 : 4 cup water.
I noticed no difference when the concentration of h2o2 were low/high as it always did the trick and I had no issues with the flower afterward (drying, curing etc.)
But this time I'm trying something new... I noticed few light gray fuzzies and I've mixed 1:3 (100ml h2o2 and 300ml plain water) and sprayed while in super late bloom :=)
Like usually, I yolo in the name of science.
matakumbaPro
Member
Just to give everyone an update. No mold, no issues, h2o2 miracolous! Inb4 I jinxed it all ^^
Wizzlebiz
Well-Known Member
I'm am flabbergasted no one got this.... fucking amazing
potpimp
Sector 5 Moderator
10 years ago
Wizzlebiz
Well-Known Member
I'm still the only like on that joke in 10 years. That's sad. It was good.
matakumbaPro
Member
What do you mean it's a joke?
Sure you lose some trichs when washing etc., but there is still plenty terps from what i can tell and as long it works it's not stupid, eh?
calvin.m16
Well-Known Member
Avoid spraying buds when possible but I'm pretty sure you shouldn't exceed a 3% strength of hydrogen peroxide solution for foliar spraying. I could be wrong but I know h2o2 is an oxidant at low concentrations and oxidants will harm terpenes, cannabinoids etc.
I've done a hydrogen peroxide wash a few times with perceivable issues to strength and aroma after cure. 3% solution diluted down from a 29% bottle.
This summer has been brutal for white powder mildew. It's infested every maple in the city and my rooms aren't meant to competely sealed, I use cooler evening air to manage temperature. I sprayed last grow in late flower with a 3% solution, the entire plant soaking wet, starting in week 7. I did it every 3 days three times and then once a week. Maaaaaybe there was a little burn on some buds, but I also started using uvb lighting. I'm sure I used too much uvb and probably was what caused the bit of burning. It also reduces yeild a fair amount, 20-30%, and the buds were all noticeably smaller.
Today is the beginning of week 8 of my current grow. I was on top of the wpm from the start. In early veg I sprayed with mineral oil, 10ml to liter (warm to hot water, shaking the shit out of the sprayer constantly while spraying) and I found this extremely effective. Once every 7-10 days. I continued until flowers started to form at week 4 and switched to a copper fungicide that was highly recommended to me by the grower who I obtained my strain from and has been growing it for 10+ years. Not impressed with it.
Last week I started to spot treat with 3% h2o2 using an eye glass sprayer. God damn, it's so effective.
I did an experiment.
I just sprayed (did not trim) the mildew spots, some smallish on leaves away from the budds, but also a number of sugar leaves had been hit pretty hard.
I usually trim this away but I left it to see what the effect would be and I was pleasantly surprised that the mildew was competely eradicated. No sign of it where I had sprayed, I took a number of photos and tagged the areas with little clips.
I continued my spot treatment while applying the copper fungicide every 3 days.
Just this morning, because of my continued disappointment in the copper spray even as I vastly increased the strength, I decided to switch to only using a 0.5% h2o2 spray (I intended to use a 1%, but I somehow goofed the math when I mixed it). I soaked the fkers, grabbing, bending, manipulating each cola so I could get every micro meter. I have found it's the buds and leaves that are just under the top bud that are most susceptible. Where the sugar leaves are exceptionally tight.
I only started using uv light again at the start of week 7, and a lot less, so this will be a much better test to see if the h2o2 has any effect on the bud size. Last grow I used from week 1, starting at 1 hour and ramped it up to 4 hours. All continuous. This just 1 hour to start and 15m every 1 hour during the middle of the day cycle. I'm going to increase it slowly all the way to harvest.
I've searched and searched the net for information, trying to focus on someone who actually applied some scientific rigor or, if I was lucky, an actual scientific paper with very little results. What I found...
1)
hydrogen peroxide is recommended and been used a lot on veggie and fruit corps without ill effect. This is just from numerous articles and many comments on forums. I didn't find any papers.
2)
bud washing with 3% h2o2 is a common practice for outdoor growers in general and for indoor when there has been wpm. 3% is the by far the most common concentration, but I have read some have used 7% or even 10%. Important to note that the plant is only in the solution for 30 seconds before been rinsed in a tub of water (or another wash of baking soda and lemon juice)
They all claim that they have not noticed any reduction in potency nor aroma.
3)
Some articles and comments about using h2o2 on flowering cannabis mention that it's an oxidizing agent and thus can and will leads to damage to the trichomes and terpenes. There's never any additional explanation or data to support this. It's difficult to put confidence in this data, especially when many growers are very loud and absolute that nothing should be sprayed on mid to late flowering cannabis buds. Which is not a bad philosophy, but perhaps results in strong opinions based on little to no data or experimentation.
Certainly, the necessity of a flush isn't substantiated by much data and is being activity questioned now. There was one "study" recently that did blind tasting and found no preference amongst experienced smokers. A highly over references weak study, in my opinion, but good that it opens up the debate and will lead to more experimentation ans data collection.
I'll keep everyone updated on my h2o2 spraying results. I'm new to this forum, so I don't know if I should just post here or perhaps another thread can be created that's more focused on h2o2 spraying experimentation.
This summer has been brutal for white powder mildew. It's infested every maple in the city and my rooms aren't meant to competely sealed, I use cooler evening air to manage temperature. I sprayed last grow in late flower with a 3% solution, the entire plant soaking wet, starting in week 7. I did it every 3 days three times and then once a week. Maaaaaybe there was a little burn on some buds, but I also started using uvb lighting. I'm sure I used too much uvb and probably was what caused the bit of burning. It also reduces yeild a fair amount, 20-30%, and the buds were all noticeably smaller.
Today is the beginning of week 8 of my current grow. I was on top of the wpm from the start. In early veg I sprayed with mineral oil, 10ml to liter (warm to hot water, shaking the shit out of the sprayer constantly while spraying) and I found this extremely effective. Once every 7-10 days. I continued until flowers started to form at week 4 and switched to a copper fungicide that was highly recommended to me by the grower who I obtained my strain from and has been growing it for 10+ years. Not impressed with it.
Last week I started to spot treat with 3% h2o2 using an eye glass sprayer. God damn, it's so effective.
I did an experiment.
I just sprayed (did not trim) the mildew spots, some smallish on leaves away from the budds, but also a number of sugar leaves had been hit pretty hard.
I usually trim this away but I left it to see what the effect would be and I was pleasantly surprised that the mildew was competely eradicated. No sign of it where I had sprayed, I took a number of photos and tagged the areas with little clips.
I continued my spot treatment while applying the copper fungicide every 3 days.
Just this morning, because of my continued disappointment in the copper spray even as I vastly increased the strength, I decided to switch to only using a 0.5% h2o2 spray (I intended to use a 1%, but I somehow goofed the math when I mixed it). I soaked the fkers, grabbing, bending, manipulating each cola so I could get every micro meter. I have found it's the buds and leaves that are just under the top bud that are most susceptible. Where the sugar leaves are exceptionally tight.
I only started using uv light again at the start of week 7, and a lot less, so this will be a much better test to see if the h2o2 has any effect on the bud size. Last grow I used from week 1, starting at 1 hour and ramped it up to 4 hours. All continuous. This just 1 hour to start and 15m every 1 hour during the middle of the day cycle. I'm going to increase it slowly all the way to harvest.
I've searched and searched the net for information, trying to focus on someone who actually applied some scientific rigor or, if I was lucky, an actual scientific paper with very little results. What I found...
1)
hydrogen peroxide is recommended and been used a lot on veggie and fruit corps without ill effect. This is just from numerous articles and many comments on forums. I didn't find any papers.
2)
bud washing with 3% h2o2 is a common practice for outdoor growers in general and for indoor when there has been wpm. 3% is the by far the most common concentration, but I have read some have used 7% or even 10%. Important to note that the plant is only in the solution for 30 seconds before been rinsed in a tub of water (or another wash of baking soda and lemon juice)
They all claim that they have not noticed any reduction in potency nor aroma.
3)
Some articles and comments about using h2o2 on flowering cannabis mention that it's an oxidizing agent and thus can and will leads to damage to the trichomes and terpenes. There's never any additional explanation or data to support this. It's difficult to put confidence in this data, especially when many growers are very loud and absolute that nothing should be sprayed on mid to late flowering cannabis buds. Which is not a bad philosophy, but perhaps results in strong opinions based on little to no data or experimentation.
Certainly, the necessity of a flush isn't substantiated by much data and is being activity questioned now. There was one "study" recently that did blind tasting and found no preference amongst experienced smokers. A highly over references weak study, in my opinion, but good that it opens up the debate and will lead to more experimentation ans data collection.
I'll keep everyone updated on my h2o2 spraying results. I'm new to this forum, so I don't know if I should just post here or perhaps another thread can be created that's more focused on h2o2 spraying experimentation.
calvin.m16
Well-Known Member
All that is doing is killing any powdery mildew that is currently on the plants. If your sucking air in from outside without HEPA filtering it then its going to just keep reinfecting your room. You need to 360 degree bomb the whole room with the zerotol wearing a gas mask and protective equipment and get something that filters your intake, then start sealing any air leaks in your grow.
Maybe consider building a proper sealed grow with no outside air being pulled in.
Ductless Mini-Split air-conditioner
Dehumidifier(s) (size the dehus by how much water you feed + 20% for ambient moisture)
I won't step foot in any grow other than mine but ESPECIALLY an unsealed grow because they are usually contaminated without a doubt.
p.s The spores are EVERYWHERE if you find them SOMEWHERE so assume they are in every crack/crevice/surface in your whole growing environment and treat it as such, that's why I recommend using a fogger with zerotol, full protective equipment and spray that shit like your painting 360 degrees and don't miss a damn spot. The powdery MIldew doesn't only exist on the plants its going to be all over your room, tryas, pots, pans, fans, filters, etc if its present at all. Think of it like germs in a public bathroom.
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Thanks for the info. I have certainly learnt from the mistakes from this grow room and I'll be making large adjustments in the future. I probably won't even grow in this one during the summer again.
I'm so looking forward to a deep deep clean. A fogger I think is the only way, I'm excited to try one out. Would sulfur accomplish the thing as zerotol. Pesticides and fungicides are restricted to commercial growers here.
