Any powdery mildew experts?
- Thread starter budulike
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GroErr
Well-Known Member
A long time and simple cleaning materials even bleach won't work effectively unless you get every spore.
There will be many opinions but from my personal experience for 4 years in an area that has so much PM outside that bushes turn white by the end of the summer, there's one effective way to get rid of it and keep it out. Sulfur burns between runs. I run them for 1.25 hours in between runs when the room is empty and spray my veg plants before coming in with a baking soda/oil solution and haven't seen it in a year or so since I've been doing this.
Prior to the sulfur burns, no matter how much I cleaned or sprayed, it was always present, maybe not as bad as a full on infection but I would see it here & there, particularly on some strains that are more susceptible to it, mainly indicas ime.
It stinks but it's effective and dissipates pretty quick once you finish a burn and turn on your fans/exhaust. it basically fills the room with a cloud of smoke which gets into every crevice and kills everything in the room.
The problem with PM is if it's in your area (outside), short of stripping down every time you enter your grow area, you'll track it in. The spores are air borne so it's pretty well impossible to keep it out of your grow area. Needless to say unfiltered outside air is a killer if you have it outside so avoid brining in fresh air from outdoors, even in winter.
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OldMedUser
Well-Known Member
Can exist for decades until conditions are right for it to proliferate again.
You can scrub your room hospital clean and fresh spores can drift in with the next waft of fresh air. We are surrounded by spores of all sorts of molds, fungi, mildews and all sorts of bacteria and virus that don't cause problems until conditions line up to allow them to grow. High humidity and heat make it easy for these things to gain a foothold on our plants and mess things up. Cooler temps and low RH go a long way to keep them at bay.
I feed my plants silica to help them repel disease and make them stronger. It can also be sprayed on the plants to make the pH on the leaf surfaces too high for mildew to flourish. I used 1ml/L of Rhino Skin recently to get rid of mildew on some clones a friend gave me. Not sure if it was powdery mildew but was something like it and it was gone after one application.
You can scrub your room hospital clean and fresh spores can drift in with the next waft of fresh air. We are surrounded by spores of all sorts of molds, fungi, mildews and all sorts of bacteria and virus that don't cause problems until conditions line up to allow them to grow. High humidity and heat make it easy for these things to gain a foothold on our plants and mess things up. Cooler temps and low RH go a long way to keep them at bay.
I feed my plants silica to help them repel disease and make them stronger. It can also be sprayed on the plants to make the pH on the leaf surfaces too high for mildew to flourish. I used 1ml/L of Rhino Skin recently to get rid of mildew on some clones a friend gave me. Not sure if it was powdery mildew but was something like it and it was gone after one application.
sparkygeek
Well-Known Member
Spraying the leaves with a Potassium Bicarbonate/water solution makes the leaves less hospitable to PM... Also, significant airflow reduces the ability of the spores to attach. It probably also reduces the humidity near the leaves caused by respiration or a rapid drop in temperature. If you haven's seen it, Cervantes has a good video of treating it at harvest... Best of luck!
iv been using silicon but could never find a recommended dose for folier spraying. I use 1ml in 1l of milk/water with few drops of h202.
I think air circulation has been my problem. I now think could I get another fan in there as opposed to could I get away with one less.
Will sealed room with ac and c02 be better option, or will I get more pm?
I think air circulation has been my problem. I now think could I get another fan in there as opposed to could I get away with one less.
Will sealed room with ac and c02 be better option, or will I get more pm?
sourdieselyumyum
Well-Known Member
My bud told me a ozone generator would kill all the spores in a given area don't know if it's true tho
Jimmy Sparkle
Well-Known Member
Fuckin rad set up my guy . You made this?Sulfur burner ran at lights out on timer. Try to prevent it happening to begin with by running a big dehumidifier 24/7 in there.
Jimmy Sparkle
Well-Known Member
Sulpher is a very toxic and corrosive gas when burned. It instantly changes p.h on everything it touches , attaches to everything because its mostly gas, gets in,on and around everything [ this is why its very effective] and must be cleaned off everything because it being corrosive. I love,love,love sulpher as a treatment and preventative.... good shit maynard lol
Dr. Who
Well-Known Member
PM once growing on a plant - is actually systemic.....It'll never simply die on that plant....it'll keep coming back...
Sulfur burners are great for use to sanitize a grow for the first time before you use it......Use it while plants are running - never! Useless anyway.- systemic remember!
Once the plant has it - it'll have it till you harvest it. A weekly spraying of a weak bio tea will keep it from expressing the surface flowering of the fungi to spore.
Running below 45% RH helps but, is no guarantee of anything!
Sulfur burners are great for use to sanitize a grow for the first time before you use it......Use it while plants are running - never! Useless anyway.- systemic remember!
Once the plant has it - it'll have it till you harvest it. A weekly spraying of a weak bio tea will keep it from expressing the surface flowering of the fungi to spore.
Running below 45% RH helps but, is no guarantee of anything!
Norby Grown
Well-Known Member
PM isn't systemic. I cleared it from my perpetual grow with eagle 20 using it 2x sprayed in veg. Got rid of (killed and burned)everything in flower but it's been gone from my perpetual grow for well over a year now.
Also the PM that attacks MJ is a certain species that doesn't attack other plants. The PM you see on clover or on the squash plant in your backyard isn't the same species that attacks MJ.
I sprayed coconut oil in the corners and along the walls to catch any spores that may have still been floating around. Keeps the dust down too.
Also the PM that attacks MJ is a certain species that doesn't attack other plants. The PM you see on clover or on the squash plant in your backyard isn't the same species that attacks MJ.
I sprayed coconut oil in the corners and along the walls to catch any spores that may have still been floating around. Keeps the dust down too.
chemphlegm
Well-Known Member
I installed a proper sized dehumidifier, set it and forget it. mold does not flourish in my rooms. Its crazy shit man, these new technology dehumidifiers work wonders to keep rh below comfortable mold spore preference.
I brought a mj plant with visible pm on it from outside two summers ago. It was still vegging about 3 feet tall and many covered leaves.
I used the hose to squirt it off, then I used some soapy water in a bucket and literally dipped and washed it gently, shook it off, sun dried, still running that gem now, two years later, never seen any mold on it or any other plant in the grow. it doesnt matter how hot or cold or humid it is outside...my rooms are controlled. when this stops working I'll throw in the towel, till then, it IS WHAT WORKS.
I brought a mj plant with visible pm on it from outside two summers ago. It was still vegging about 3 feet tall and many covered leaves.
I used the hose to squirt it off, then I used some soapy water in a bucket and literally dipped and washed it gently, shook it off, sun dried, still running that gem now, two years later, never seen any mold on it or any other plant in the grow. it doesnt matter how hot or cold or humid it is outside...my rooms are controlled. when this stops working I'll throw in the towel, till then, it IS WHAT WORKS.
chemphlegm
Well-Known Member
I understand "PM"-powdery mildew covers many types of fungal growths? do you know if the ones that occur in grow rooms are always the same strain of fungi as the next indoor room infection?
Norby Grown
Well-Known Member
As far as I know PM talked about here is a certain specie of mildew that infects MJ and a few other plants. There are a bunch of different mildews that affect other plants but pm isn't botrytis or any other mold that may affect cannabis. The PM that can affect cannabis is the same that can affect hops and a few other plants so it can be hanging around an area that grows these other plants and spread but the PM on clover or squash is not the same that will affect your MJ plants. Spores aren't everywhere just waiting to infect. I never had it outside or inside growing back in NYS and it was on a lot of other plants and the conditions were right indoors and out. I lived in a flood plain that was a very humid area. Only time i ever got it was here(in Mi from a clone) and I got rid of it and it never came back and conditions have been right from time to time to get it back here. It was also below 50% humidity when I got it here.
NrthrnMichigan
Well-Known Member
Is this Hokum?
Saw this the other day. Thank goodness and knock on wood pm hasn't found my grow space.
chemphlegm
Well-Known Member
UV light will destroy mold. However, one must have two things — UV light intensity (which decreases rapidly with distance from the bulb) and “dwell time” which is the time that the mold spore is actually exposed to the UV light. The amount of exposure time required to destroy the mold varies greatly for the different types of mold. Some molds are destroyed after a few seconds — others require 8,000 seconds or more. The air traveling in an air duct is moving at a minimum of 100 feet per minute. What are the chances that a mold spore in the duct will be exposed to the UV light for a sufficient length of time? Pretty slim. UV lights have been shown to reduce mold when exposed continuously to the coils of the HVAC system. Cleaning the coils periodically would accomplish the same result.
stick some bread in a test tube under a UV anti mold bulb.....it grows mold man, I dunno.....
stick some bread in a test tube under a UV anti mold bulb.....it grows mold man, I dunno.....
NrthrnMichigan
Well-Known Member
I had a hard time believing this video while watching.
chemphlegm
Well-Known Member
I think its one of those things that , In theory it works, but not enough to skip other sources, the real issues are always evident, and mold is not caused by the lack of UV light for sure, thats a good place to start. mold will not flourish in a controlled room, I promise, I prove it daily since years ago. its not rocket science, just growers skipping controls for the nickel saves
with the right heat, ac, feeding program, cleaning, rh etc controls....i never gets right for mold. Like I said I brought a pm plant into my grow room cured, . I put her clones right next to my perpetual trays of clones....still do.. would she be the first to mold if I jimmied my controls? I dunno, but why would I do that
Norby Grown
Well-Known Member
Make a 10gal tank with 3/4 of the lid covered and fill with a little water to increase the humidity. You'll know in a few days if it was still around if it was powdery mildew and it stayed around. Just washing it off good outside before it came in could be enough to eradicate it. It isn't systemic.
chemphlegm
Well-Known Member
yep, you think that another plant in that wet enviro could also express pm fungus?