Powdery Mildew In A Perpetual Grow

[Norby]

Where to start?  I got PM in veg and in flower.  Took out 4 from flower which only had a few spots on them and burned them along with half of my veg room(even though there were only a few spots on one or 2 leaves per plant). Have 3 that are within a week of coming down 2 of which I found 2-10 spots on the plants with a loupe, not really even noticeable to the eye(except the one leaf which I cut the whole bud and tossed).  The other one seems resistant so I'm not too worried about her, not a spot anywhere and she's loosing N and ready tomorrow or the next day.  I removed the leaves with spots after spraying them with potassium Bicarbonate and spot hit any leaves that looked suspect on the ones close to ready.  I was told at the grow store to hit these 2, that are coming down in 5 days, with milk so that, after they were dry, the PM wouldn't take them in the jar curing.  Does PM present a problem on dried flowers if there were to be a couple spores present with no active infection?  I didn't think that PM would affect any dried flowers since it needed the nutrients from the cell to thrive and multiply.  Either way, tehy are going into a vacuum sealed mason jars for storage.  Without air any bacteria or spores, etc. wouldn't be able to live anyway. 

So first question, can PM affect drying/dry flowers if the humidity is 35-40% and there is no visible infections anywhere?

 

Next, I hit everything that's less than 2 weeks into flower and all veg with Neem oil the first night I noticed.  Second day I got my Ph up(potassium Bicarbonate) and mixed a teaspoon per quart of Ro water, which raised from 5.9 to 8.6 ph, and added about 15 drops of peppermint castile soap and sprayed everything again, plants, stems, soil surface, buckets, everything.  With the 4 plants destroyed out of flower the plants are spaced so tehy don't touch each other.  I added another fan and left the back flap open on the tent with the dehumidifier set to 35% blowing into the tent.  I also watered with Pro Tekt 0.0.3 from dyna grow.  Supposedly silica adds to the cell wall and toughens it so that the PM can't get it's hyphae? thru the cell wall to draw nutrients.  I probably could've saved more but decided to go for the kill so I don't have to deal again in the spring or summer.  Sulfur burn will come in a few days once teh last in flower are out.

 

What I've found from this is that my Larry OG seems to be completely resistant.  The Grapestomper OG X Purple Kush was next in line.  I don't know if it was the botanicare that I mistook as PM but I was in a whirl cutting anything that wasn't completely necessary and one of them in veg got cut.  The one in flower doesn't have a spot and it's in sad shape finishing it's cycle, should be the best target.  The "papery leaf" strains seemed to have the least resistance.  Bubble Queen, one of my plushberries, space dawg, pennywise and one grapefruit badass were all hit.  One pennywise and one grapefruit badass didn't have any spots in flower but I think the veg ones did.  I had one bus tray with 6 in it overlapping and they all got hit with it since the bubble queen was so susceptible and right in the middle of all of them so they all went. 

 

So it got me to thinking, can you preserve spores in the freezer indefinitely? I wouldn't mind keeping some in a sealed container to test my strains in the future and come up with resistant strains, maybe only breed resistant strains.  So do you think the samples should be dried first or just frozen on a fresh leaf, if I can find one now?

 

As for sulfur burners, how long and how often?  And do you remove things like magazines, shelves and fert bottles, etc.?  Can you actually feel any film on anything left in the room?

[Big J]

I have found my best friend in the world for dealing with this. I received a clone beautiful clone ran her, Treated the plant just like they got neem treated and I always use 50% alcohol to wash the following day been doing that since I got mites once I don't see those gentlemen anymore that way. grew her out got clones flowered the clones bam PM. Then every plant I had did that.

 Until I found out about UVC lights.  I bought a CFL UVC bulb and a light with a metal shield and UVC protective glasses. I just shine the light at the plants moving at a decient pace wave it over the entire plant and the tent. I have had it come back so I missed a some somewhere. But I just do that twice a week and I have not seen it in months. I also use the bulb to deodorizes my shoe closet. I just hold the opening of the shoe over the bulb real quick the same days and no smelly shoes. 

 

Now listen though. This thing is dangerous. UVC IS VERY BAD FOR YOUR SKIN AND EYES!!!!!! Always wear protective clothing long sleeves and gloves, and UVC saftey glasses are a must.Try to never point it at yourself or anyone else I used the light with no shield and my face got sunburned and peeled the next day. IT'S BAD STUFF.

 

If you use it right it is amazing though and works like a rock star. 

 

I just got the stuff off amazon and put it together myself but there are some designed for growing with a nice shield blocked on 3 sides of the bulb and high dollar ballast and molded handle super nice but like $200 to $300. I have less then $50 into mine with the glasses. I am building a new shield with a 3 side block on it with and handle I will make with a dowel that is comfortable for my hand. 

 

Also due to this I cut back on my numbers and just let them veg a bit longer. Open them up and let them shine. I get close to the same amount with less plants. 

 

Be safe and have an amazing time growing. So relaxing and frustrating at the same time but worth the effort in the end. Enjoy the journey.

[t-pain]

if you took an electron microscope , you'd probably see PM spores on your dried flowers.

 

have you been breathing in PM spores already? yes.

 

no idea if you can save PM in a freezer. seems like an easy way to reinfect your grow room if you do not have a biohazard suit and follow decontamination protocol

[Norby]

I have found my best friend in the world for dealing with this. I received a clone beautiful clone ran her, Treated the plant just like they got neem treated and I always use 50% alcohol to wash the following day been doing that since I got mites once I don't see those gentlemen anymore that way. grew her out got clones flowered the clones bam PM. Then every plant I had did that.

 

 Until I found out about UVC lights.  I bought a CFL UVC bulb and a light with a metal shield and UVC protective glasses. I just shine the light at the plants moving at a decient pace wave it over the entire plant and the tent. I have had it come back so I missed a some somewhere. But I just do that twice a week and I have not seen it in months. I also use the bulb to deodorizes my shoe closet. I just hold the opening of the shoe over the bulb real quick the same days and no smelly shoes. 

 

Now listen though. This thing is dangerous. UVC IS VERY BAD FOR YOUR SKIN AND EYES!!!!!! Always wear protective clothing long sleeves and gloves, and UVC saftey glasses are a must.Try to never point it at yourself or anyone else I used the light with no shield and my face got sunburned and peeled the next day. IT'S BAD STUFF.

 

If you use it right it is amazing though and works like a rock star. 

 

I just got the stuff off amazon and put it together myself but there are some designed for growing with a nice shield blocked on 3 sides of the bulb and high dollar ballast and molded handle super nice but like $200 to $300. I have less then $50 into mine with the glasses. I am building a new shield with a 3 side block on it with and handle I will make with a dowel that is comfortable for my hand. 

 

Also due to this I cut back on my numbers and just let them veg a bit longer. Open them up and let them shine. I get close to the same amount with less plants. 

 

Be safe and have an amazing time growing. So relaxing and frustrating at the same time but worth the effort in the end. Enjoy the journey.

I was thinking of using the old water sterilizer from my house as a uv air sterilizer by just using a fan on it instead of piping it into  the water system.  I don't trust myself with equipment like that(not contained).  Good to know though, thanks for the account.

[t-pain]

what i've heard people using those uvb/uvc lights is that they just setup an automatic door switch or light switch so the uv lights turn off automatically when you open the door, or you just switch it off before walking in.

[AbominableDro-Man]

I would be particularly mindful however if you happen to have any patients with respiratory issues or allergies to molds, any little bit left on the flowers could really set off some havoc.

[t-pain]

people who get budrot and PM sometimes make hash, hoping that the process (either water/ice or heat) renders some of the spores non harmful.

 

i tried looking for some info on toxicity of PM spores but got nowhere.

possibly respiratory problem, allergy problem, etc.

[Norby]

  I getcha but the PM spores are less in #'s than common mold spores in the air at this point.  The last thing it hits is the buds and it didn't even get more than a spot on a dozen leaves, you needed a loupe to see most of it.  If someone was that sensitive to PM spores they couldn't walk outside this summer as the clover was covered this year and one breath outside would get more PM spores than what's in my whole basement.  Luckily that PM doesn't hit MJ.

 

  But no, no one in my registry has respiratory issues and if there was something that would cause a problem it wouldn't get out the door.

[Norby]

Oh, and they did all find me here so they could read up on what's up, but they did get an update about it about 3 hours after I found out while I was taking a break.  I copied and pasted an email and sent it out to all of them.

[Dlo]

As for sulfur burners, how long and how often? And do you remove things like magazines, shelves and fert bottles, etc.? Can you actually feel any film on anything left in the room?

 

 

IMO

Sulfur burn at lights off for 4 hours ever third day for two weeks. I would leave every thing in there so it gets covered too. I don't think you'll be able to feel any film on anything. I think you can save everything that's under three weeks in bloom.

[garyfisher]

myclobutanil

[trichcycler]

...just one drop in both eyes.....you'll never see microscopic mildew in the garden again!  

[free420country]

I have a homemade sulpher burner and it worked after one good use. 3/4 cup sulphrr pelets in a soup can set on a heat lamp.

 

I used a 70 watt heat lamp mounted in a large coffe can then set the soop xan full on the bulb. I ran it on a timer four 4 hours. With no ventilation then for 3 more hours with my fans on.killed it quick and that amount did my hole basement.

 

 

Ps dont breath the vapors or go anyware near it untill the room is well vented.

[Norby]

Took down 2 today.  One showed no signs whatsoever.  Grapestomper OG X Purple Kush.  The leaves were on their way out too.  Perfect target.  Probably pretty resistant.

 

The Space Dawg on the other hand.  Papery thin leaves and I found about 10 spots throughout the whole plant.  It's down about a week early.  I'll probably make all my edibles from this one.  Thinking oil and filtering.  Think I read that a coffee filter would filter out all the spores.  Of which there will be very few, unless it hits during drying.  I'm pretty sure any colonies I saw were inactive and just sporing out since it's been <35% humidity for 3 days now. 

 

The last of the untreated plants is the orange creamsicle.  Saw 2 spots on this one and sprayed with K Bicarb 2 days ago and not a spot on it today.  It should be done in another 2-5 days.  I'll check it every day till then.

 

3 plants that don't fit into the under 3 weeks in flower are the gorilla glue #4 which has been spotless, the Grapefruit Badass, which had one spot and the pennywise which didn't have a spot on it.  All 3 were sprayed with K Bicarbonate.  Guess I'll just put them into a tent outside the room for the sulfur burn and maybe spray them one more time with the Potassium bicarbonate while the sulfur burn is going and watch them like a hawk and think of ditching if I see anything.

Edited January 13, 2015 by Norby

[trichcycler]

Norby,

 

after you manage the symptom of powdery mildew, what steps will you take to avoid the problem of high humidity/ low temps  in the future ?

[Norby]

Keep the heater at 70 at nite(keeps about 73) and keep the dehumidifier on at 40% blowing in the back flap.  It was at 40% before when I got it.  The tent being closed with a 6inch filter/ventfan was probably what started it.  I don't think it would've got over 60% humidity in there with the rest of the basement 35-45% though.  I'm keeping the plants not touching(1/4 less plants, not replacing the ones I cut out) each other and trimming up the bottoms for better air flow.  They were on buckets so i thought the lower growth wouldn't be a problem but doing all I can now.  It'll keep trim times down too.

  Adding a little silica to thicken up the cell walls a bit too.  Considering it's kinda like a foliar feed, continue spraying the ones in veg with K Bicarb once a week.

[trichcycler]

I'm surprised you saw any pm with ambient 35-45%, that will be a little more difficult to remedy. more moving air, a little warmer maybe when lights off.

 

I had a friend(?) get hit pre dehumidifier of course, and I helped him by removing the flowering plants, discarding moldy ones,warmed the room, sprayed neem oil on the infected plants, and fired up the sulphur burner the next day, and rinsed the room and plants with water the day after that. 100% success with no film, taste, smell, nothing but decent buds and NO poisonous sprays!

have you considered turning the dehumidifier the other way, sucking out of the tent ?

[Norby]

The dehumidifer wasn't blowing in the back flap of the tent before.  A 6 inch stink soc vent was taking air out and the bottom flaps and one 4 inch cyclone fan venting in.  I think I'll be able to close it up now that they are spaced better and another fan was  added.  I won't till after the Sulfur though.  Basically the tent was too crowded.

 

I got it before in my shed and cut everything, added a dehumidifier and started without even cleaning, just new soil and never got it again.  Till now.

Edited January 14, 2015 by Norby

[Norby]

New plan.  I was under the false assumption that a sulfur burn would sterilize the room of spores.  Since this isn't the case I decided to use Potassium Bicarbonate to spray down the tent and then take teh tent down and put it away.  It was hindering airflow.  Now I will build a wall to section off a 10 x 12 room where the 8x8 tent was.  this way the dehumidifier is in the room and there will be more room to put fans in and position carbon filters etc. 

I wanted to paint the basement before i put up the tent, but forgot.  So I'll move the tent into the basement open area, lock the plants in there.  Then I'll paint the area where the tent was after I put up the wall and paint the walls.  I'll spray everything I don't paint with Potassium Bicarb.   Then I'll spray the tent and plants in the basement.  Then I'll do then same with the veg room, using the flower tent as a staging area.

 

For me it'd be a little too worrisome if I didn't do most everything I could to make sure no spores would kick up and reinfest the garden.  I'm already resigning to the fact that I can't sample a strain from a dispensary without worrying about introducing something.  I'm pretty sure that's where it came from, a sample of Ghost Train Haze.  the more I think about it, it may have been a little too "resinous" from my memory, or too "white" I should say.  It would've been around the time I was taking cuttings from a plant I was putting into flower.  The spots on the plant, which was first to show, could've been from where I touched the leaves to get the cuttings after packing a vaporizer of ghost train haze.  Either way, my garden was vulnerable to the point of where it shouldn't have been, either thru conditions or practices of bringing in infected meds to try out.  Should've just bought the cut and sprayed it or got a pack of seeds. I even broke my rule of trying something that I didn't know how it was grown.  And it looks like karma has got me for it.

[trichcycler]

PH......

 

 

but a simple bleach cleaner spray will kill spores. spray your stink sock/can also, and ductwork, slush buckets, etc.

[garyfisher]

neither sulfur nor KHCO3 will kill PM.  It will cover it up for a few days but you will have to continue to spray for as long as you keep the infected genetics around.

 

IMO, Sulfur works better more long term than KHCO3.

Bleach will not kill the spores.  This is a common misconception. 

If you really want to fix this problem, dump all your plants and start over fresh OR spray your veg plants with Eagle20 and be done with it.

 

 

To add,  Spores are ubiquitous in nature.  Unless you're growing in an aseptic environment, there will be spores present.  The solution is to discourage growth by maintaining proper conditions for plants not fungi.  Fungi thrives in humid conditions that lack fresh air exchanges.

Edited January 15, 2015 by garyfisher

[trichcycler]

chlorine kills mold spores, so does water, and even oil.

chlorine may not be the best clean up agent inside mold infested areas and covered walls/porous surfaces. op has a few almost invisible spots on a few weak/neglected plants. The spores infecting these plants is ever present.

 

 

 

"To add, Spores are ubiquitous in nature. Unless you're growing in an aseptic environment, there will be spores present. The solution is to discourage growth by maintaining proper conditions for plants not fungi. Fungi thrives in humid conditions that lack fresh air exchanges."

 

 

Right On !

[garyfisher]

you underestimate how adaptive fungi are in nature.  These are the fastest evolving organisms in the world and certainly will outlive the human species by consuming our toxic waste.    If intelligence is measured in an organisms ability to survive, then fungi are the most intelligent creatures we have discovered.

 

Chlorine bleach is known to kill one kind of spores only; that is ONLY on nonpourous surfaces when treated for a certain length of time (30minutes). Water will certainly not kill a spore, it will encourage it's growth.  And oil?  Eh..  I've seen mold grow on oil left in a frying pan as well as plants treated with oil sprays.  I've seen a half dozen patients with PM issues treat with all sorts of oils including: styleT oil, Organocide, Neem, Heavy16, fruit and tree spray .  None of these products have stopped PM.  It usually knocks it down for 2-5 days but you will have to spray once a week until harvest.

 

PM is systemic.

Edited January 15, 2015 by garyfisher

[Hayduke]

Only thing I ever found worked was Eagle 20.  It is for turf management, and absolutely not for human consumption.  Cut a clone, treat it with Eagle 20 and then when big enough, clone again.  It works well, but is petroleum based, so you must take care and caution...

 

Other than that, throw it all away and start over.

[Wild Bill]

Here's a fairly concise overview of powdery mildew from Colorado State University.

 

http://www.ext.colostate.edu/pubs/garden/02902.html