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Can we please make a Sticky for Powdery Mildew, Bud Rot, etc...

JBLAZEC0

New member
Working in a large commercial grow that had a pm problem, we found the most effective weapon to combat pm is h2o2...or commonly know as hydrogen peroxcide...it will kill the spores on contact, it's cost effective and safe to spray late in flower.
 

highbrid1

Member
Does burning sulfur work for killing spores etc in unused grow areas or is it only effective for treating plants in grow rooms?
 
I guess im a lttle late to the game, but their is a cheap, relatively safe product that kills pm on contact and prevents its return. If you see it today, spray it today and its gone tommorow - forever.

Liquid Copper is used for organic gardening and is a death sentence to Pm, botryitis, powdery mildew and about any other fungal/bacterial disease.

For the past 30 days, my temps have been running in the mid 90's straight with jsut over 11 inches of rain during the period. Todays forcast: 95 degrees W/ 3" of rain likely. If you hang clothes on the line they will turn green/fuzzy with mould - its on everything, everywhere. Keeping mould off of big plants is a tough job but LC knocks it out.

Having very good results with a duel attack of H2O2 (Peroxide) w/ baking soda (BS) to sterilize the plant. 1/2 cup H2O2 + 1 tsp BS per gal.

Then followed up with Liquid Copper as a protection layer.

I would have thought the plants would be a burnt mess after spraying these items BUT they are looking MUCH more happy after the sprays.
 

ninjasmoke

New member
Which strength h202 are you using? Can I spray it in a crop that is 5 weeks in flower? Will it hurt the bud?
 
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grapeman

Active member
Veteran
Working in a large commercial grow that had a pm problem, we found the most effective weapon to combat pm is h2o2...or commonly know as hydrogen peroxcide...it will kill the spores on contact, it's cost effective and safe to spray late in flower.

You will find that just spraying water (H2O) will do the same as spraying H2O2.

It's the water that kills spores on contact and not the H2O2. Just fill your sprayer with water, add a surfactant and spray. Kills PM on contact.

Also, I've never heard of "fake" PM.
 
3% HP

its my first year using peroxide but loving what im reading & seeing so far.

its your call but I would spray 1/2 cup HP per gal the last week if there was fungus on the buds.

test some & see ?
 

sub dermal

Member
well shit. the PM i've dealt with on my green crack has all been on the top side of the leaves. i hope eagle 20EW works for that too...

Andl, some pictures would be great.

.sd
 
Botrytis is out very quickly after these massive rain storms & this OMRI stuff isn't working.

Anyone having any luck slowing down these nasty spores ?
 
need a lil advice.
about 6 months ago a started to have problems with pm as well as bud rot. i started to use sulfur/water spray once a week but this didnt really seem to clear it up. after a few weeks i built a sulfur burner and that seemed to do the trick. now this is my problem, i didnt realize sulfur dioxide is really toxic. i grow in a few mills pride-like cabinets that are in my bedroom. do to security issues, i cannot move them anywhere else. once i realized SO2 was bad i stopped using the burner and went back to the spray. the mold came back within a few weeks of stopping the burning. i then started using pro-tek as a foliar spray and hitting the girls with the pro-tek and the sulfur sprays once a week. been doing this for a few weeks now and i just culled a few yesterday because of bud rot. im almost at the point of using the burner again just cause i know it will work, but i dont want to endanger myself. how toxic is SO2? should i add H2O2 to my sprays? is there something else i should be using to combat this?
 
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Cheesus Crust

New member
I have an outside grow infected with what i think is PM. Its all bag seed, and unfortunately, I don't have any pics or real specs. I haven't given them extra nutes, just de-chlorinated tap water. They were germinated once or twice early on (accidentally), but as the buds grew around the maturing seeds, the dead seed pods attracted mold. Some of the dying fan leaves are getting moldy on the dead spots, but i remove the dead leaves moldy or not. I also have had some buds die, (bud rot maybe?) so i've been clipping those and checking for worms. two dead buds did have some cob webby mold, i forget what kind that is. I clipped that entire branch. Almost all of my plants seem to have at least one moldy seedpod, probly more, so im wondering should i harvest now and salvage what i can? I am a total newb, and will gladly take any help. Again, sorry i dont have pics or real specs. I'm not even sure about how long they've flowered. i will try to put some pics up asap
 
"need a lil advice.
about 6 months ago a started to have problems with pm as well as bud rot. i started to use sulfur/water spray once a week but this didnt really seem to clear it up. after a few weeks i built a sulfur burner and that seemed to do the trick. now this is my problem, i didnt realize sulfur dioxide is really toxic. i grow in a few mills pride-like cabinets that are in my bedroom. do to security issues, i cannot move them anywhere else. once i realized SO2 was bad i stopped using the burner and went back to the spray. the mold came back within a few weeks of stopping the burning. i then started using pro-tek as a foliar spray and hitting the girls with the pro-tek and the sulfur sprays once a week. been doing this for a few weeks now and i just culled a few yesterday because of bud rot. im almost at the point of using the burner again just cause i know it will work, but i dont want to endanger myself. how toxic is SO2? should i add H2O2 to my sprays? is there something else i should be using to combat this?"

after doing a lil more research, i have found that H2O2 and sulfur DO NOT mix. it seems it will produce hydrogen sulfide, and not sulfur dioxide, which is even more toxic and to top it of is also more flammable. so im asking again, does anyone know if i can mix H2O2 and Pro-tek (potassium silicate K2SiO3) safely?
 

Easygrowing

Active member
Veteran
Great reading stuff !
I have working with UV-C for a while.But the beams are hard to the leafs,so i have dropped the Pl-l down in my vaccumcleaner and let him running for about 45 seconds 2 times daily..for cleaning the air for bacteria and watch about,is it better than use it in open air,so beams hit the plants..have only trying so,for a couple a days-to early to say something.
picture.php

sorry for bad pic bad cam..have also tried with chlorine and vinegaer.
 

phellowship

Member
im 7 weeks in flower,is there anything i can do .i was gonna wipe down the heave spots with a fungicide and a rag but im wondering if that would just spread it more.any sugestions would be gratefull for.
 
Not to be an ass, but alot of the stuff being kicked around here is going around the mountain again. Eagle 20 by day 14 of flower and you will forget PM exists.

Talking about fake vs real PM seems like more cannabis lore created in underground bunkers by people making up science as they go along - to my knowledge it is not grounded in biology and newbies would be best by striking that comment from their mental hard drive and just remember:
1) PM is everywhere, take measures against introduction as management of infected stock is a losing battle

2)PM is systemic, it is in the cellular structure of the plant, only thing that could cure would be a systemic product. When you spray/wipe/sulfur bomb a PM infected plant, and the leaves are clean of PM dust...it is like having a cold and taking a shower to wash your nose and lungs out good. You may look clean and feel clean, but you are still sick on a cellular level, and within 60 minutes you will have red eyes, and snotty nose, and phlem in your throat again. The PM dust will be back because it still exists in the host plant EVEN though you dont see any white mildew.

3) LOTS of short term cures with varying levels of effectiveness and toxicity to people and plants - read up on safer close to harvest ideas...h20, milk, greencure

4) Spray as close to sun-up/lights on as you can so they have the heat of the "day" to evaporate the excess h20 of surface plant tissues and transpire the moisture out of the buds.

5) Some white papers on fake vs real PM would be nice given how ubiquitous PM is, I love learning new stuff. I await the data anxiously....

Eagle wont help you folks in week 7 _ I understand and I am sorry - but all is not lost, it just takes more work. Grapeman fights this shit on grapes 24/7 - listen to him, he speaks wisdom on this subject. You can spray with h202, but be aware if you use h202 too strong it oxidizes stuff and turns pistils dark brown and any non-living tissue (plenty on leaves on older plants, little rust spots etc) will rapidly oxidize and spread making the plant look shitty. It wont hurt much in reality, but if you are intending your product for market in any capacity it could effect appearance - I speak from experience here.

Greencure can help some...not really a cure for PM, but can help to discourage botrytis and other molds since you will have water sitting on the buds, but I am not convinced greencure is needed to knock down the PM as much it helps to inhibit mold-set when your buds are wet from spraying the PM with h20.

How to kill powdery mildew forever. https://www.icmag.com/ic/showthread.php?t=161425

Your mileage may vary...Peace.
 
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Any idea how long Eagle20ew keeps? I've had an unopened bottle for 2 years. Also, is there any clarity on the ideal ratio of milk to water and the type (skim/whole/buttermilk) for a spray? What's a good ratio for baking soda/water? TIA
 

vapedg13

Member
Veteran
This is what I did and it worked for me


In a 32 oz spray botttle of water add 1/2 cup of 3% peroxide (h202) & 3 scoops of greencure...spray 100% of your plant

IMG_1609.jpg


SmallScoop.gif


The greencure kills the spores on contact...the h202 raises the plant ph kills it from the inside

You will need to totaly clean your Growroom... I used a Anti Fungal Bomb...Fungaflor...Works like a sulfur burner but no rotten egg smell
KGrHqVlkE2EPD5NvBNp8s-Nv1g_12-1.jpg
 
...the h202 raises the plant ph kills it from the inside

Please explain the science behind this...as I call "wives tale and grower lore" on this one - there is another name for it that I will withhold. This type of stuff is dangerous for newbies as it can allow PM to take over a crop fast if there is a belief it is now cured with h202.

- h202 doesnt kill PM because of high pH, it is an oxidizer. It works on the surface of the plant where the h202 has been sprayed. It doesn't work anywhere it doesn't make contact.

- It does NOTHING to change the pH of the media, but I am not aware of what the "Plant pH" even is. Please tell me how to measure the "plant pH", where to get an instrument to do so, and where should it be for a healthy plant as this term is new to me? :chin:

-If h202 were to somehow enter the plant in a way to "raise the plant pH", it would have to be systemic, which h202 is not. Neither is greencure or 98% of PM "cures". Eagle 20 is though. If you don't understand the nature of "systemic, you need to study more. You will never understand proper treatment of PM without a proper understanding of systemic illnesses and treatments.

- unlike h202, Greencure & milk are a pH related reaction, the high pH kills the PM upon contact, and raises the pH of the leaf surface for a short period of time inhibiting the growth of the PM spores on the leaf surface. Unless treated systemically, the PM is still in the plant, just not able to manifest the spores on the leaf while the residual spray keeps surface pH high.

I am looking forward to learning about "plant pH". Back to getting rid of PM.
 

vapedg13

Member
Veteran
when Im say it raises the plants ph... I mean it temporaraly raises the ph level of the leafs

When you spray your plant with h202... it is absorbed into the plant....not just left on the surface for pm control

As an example of leaf ph or plant ph....this article of leaf ph

Ecosystems Ecology

You have free access to this content Leaf pH as a plant trait: species-driven rather than soil-driven variation

Johannes H. C. Cornelissen1,*, Florus Sibma1, Richard S. P. Van Logtestijn1, Rob A. Broekman1, Ken Thompson2Article first published online: 12 AUG 2010

DOI: 10.1111/j.1365-2435.2010.01765.x

© 2010 The Authors. Functional Ecology © 2010 British Ecological Society
Issue
Functional Ecology
Volume 25, Issue 3, pages 449–455, June 2011
Additional Information(Show All)
How to CiteAuthor InformationPublication History
How to Cite
Cornelissen, J. H. C., Sibma, F., Van Logtestijn, R. S. P., Broekman, R. A. and Thompson, K. (2011), Leaf pH as a plant trait: species-driven rather than soil-driven variation. Functional Ecology, 25: 449–455. doi: 10.1111/j.1365-2435.2010.01765.x

Author Information
1Systems Ecology, Department of Ecological Science, Faculty of Earth and Life Sciences, VU University Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands
2Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, South Yorkshire, UK
* Correspondence author. E-mail: hans.cornelissen@falw.vu.nl

Publication History
Issue published online: 3 MAY 2011
Article first published online: 12 AUG 2010
Received 9 April 2010; accepted 13 July 2010Handling Editor: Lawren Sack
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Share|AbstractArticleReferencesSupporting InformationCited ByView Full Article with Supporting Information (HTML) Get PDF (257K)Keywords:calcium;intraspecific variation;interspecific variation;leaf acidity;leaf chemistry;phenotypic plasticity;soil pH
Summary
1. Interspecific variation in plant functional traits is fast becoming popular as a tool for understanding and predicting ecosystem biogeochemistry as dependent on vegetation composition. Leaf pH has recently been shown to be a promising new candidate trait for this purpose. But how robust is leaf pH as a species trait in the face of environmental variation? We hypothesized that inherent interspecific variation in leaf pH should be greater than phenotypic variation of given species in response to soil environments.

2. We tested this hypothesis in a temperate herbaceous flora by growing 23 species experimentally in three soils of contrasting pH (ranging by almost three pH units) and related chemistry.

3. As predicted, there was large and consistent variation in leaf pH among these species, which was robust to the differences between soil types. Indeed both the species rankings and the absolute species values for leaf pH were remarkably constant in comparisons between soil types.

4. The fact that a given species can maintain a leaf pH very different from that of their soil environment, combined with the great interspecific variation in leaf pH, indicates that leaf pH really is largely a species-specific trait. Linked with recent field evidence we suggest that interspecific variation in leaf pH, while easy and cheap to assess, has important predictive power of biogeochemical properties and processes in ecosystems.
View Full Article with Supporting Information (HTML) Get PDF (257K)More content like thisFind more content: like this articleFind more content written by:Johannes H. C. CornelissenFlorus SibmaRichard S. P. Van LogtestijnRob A. BroekmanKen ThompsonAll Authors
 
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