Preventing Powdery Mildew

[PharmaCan]

I have a particular strain of mj that is a Master x Bubba hybrid. It's a really potent strain that I really like. The only problem is, it's highly susceptible to powdery mildew. I have six different strains of mother plants growing together in the mother cab. The MxB will get covered with powdery mildew while all the plants around it have none. I'm a couple weeks into veg on some plants that were cloned from the mother and I noticed yesterday that the leaves have a slightly dull patina to them - a sure sign that they are starting to develop powdery mildew.

I have a sulphur burner, and I have Serenade, so I know how to treat the powdery mildew. My question is, does anyone know how to prevent it?

I've been looking at Silica supplements. The propaganda says that silica helps strengthen cell walls. Would strengthening the cell walls make the plant less susceptible to powdery mildew?

Anyone have any experience with this type of problem?

PC

 

[Guest]

Try SOYANARA - Or BIO SOY M, (if you can find it - the old product). Used weekly in conjunction with Dutch Masters PENETRATOR (or some other high quality wetting agent), you will get no Mildew.

These are very gentle to the plants, and they seem to like it.

I have a strain or two that really attracts PM, as well.

Other than that, a sure fire way to keep PM under control is the use of a good DEHUMIDIFIER, primarily for use when the lights are off, but during seasons like this one, keeping it set on 50% or 45% during the "Day" is not a bad idea either.

And empty it daily.

If you do these things, you will not see much PM except maybe at the end, when you are well past the point when you can spray buds.

But, with a very late start, the PM will not really get into the buds. Just a couple of spots will show.

I found Serenade to impart a sickening taste to the buds.

Good luck.

 

[Guest]

neem oil

 

[Pirate138]

neem oil

Ive never heard of neem oil being for mildew....only pests.

 

[Bean Bagpipe]

I just spray my plants with water with a ph of 8, everyother day or so....and i never get it anymore. It seems like the mildew cant grow.

 

[Core]

lower humidity...

 

[coop]

milk/water mix?

 

[Bean Bagpipe]

I should add that its incredibly, nose crackingly, dry where i live, so the water is not really a problemo.

Never heard of a water/milk mix...? Like, cow juice milk?

 

[fisher15]

Just picked up a dehumidifier today, so we'll see how she works...

 

[PharmaCan]

Thanks to all for the replies!

According to what I have read about powdery mildew, there are a plethora of varieties of PM, each one more or less specific to a certain plant. PM spores are carried in the air, more so on a windy day. Last summer I got PM during high winds when the ambient temps were 110+ and the humidity around 30%. My humidity gauges show humidity that sometimes approaches 60%, but is usually in the 45% - 55% range. Right now the RH is 31% and today I had to treat PM on some vegging plants.

icysurfer - Thanks for the tip. I found Bio Soy M, but it was an old page and the "buy me" links were dead, so I need to try to track down where to buy it. Searching for anything with "soy" in the name is problematic - too darn many results. ...and searching "Soyanara" gives interesting links to Japanese culture, but didn't mention plants at all.

Bean Bagpipe - As I understand it, one of the things the sulphur treatment does is to change the pH on the leaves and then the PM can't grow. If you are misting with pH 8.0 water, it is probably accomplishing pretty much the same thing. ...but I don't know if I want to mist my plants every other day. I try to keep the RH in the cabs at about 50% and I don't think that's dry enough to get away with frequent mistings.

fisher 15 - Were you having problems with PM? What % RH are you setting the dehumidifier for?

Thanks again to everyone!

PC

 

[Kr@kEn]

Spraying with things only makes the problem worse in most cases. It thrives on high humidity.
YOu can use milk and water solution to PREVENT powdery mildew but it won't get rid of existing infection. The milk solution is used during veg a couple of times. This creates biological barrier to fight the mildew off. But this is preventative, not a cure.

Another thing that helps is (if possible), sprinkle a light layer of baking soda on the floor of your grow space. Baking soda is well know for fighting such problems just by sharing the air with your garden. Just sprinkle a couple of boxes on the floor before each flowering cycle. Then after you harvest, clean up the baking soda and sprinkle a new layer of it before each new crop starts to flower.

 

[Guest]

I have been living with PM, and preventing it for years, living near the coast.... It used to cost me a great deal of sleep. But no longer - it just requires work, attention, and committment.. We do not want to smoke PM..... Not at all....

One of my signature strains is an absolute MAGNET for any spores that are hanging around. Especially in the greenhouse.

If you do spray, always do it right before the lights go off, or even better, use a headlamp, and do it just AFTER the lights switch off....

Or in a greenhouse/outdoor application, best to spray right after the sun warms up the day a bit, but is not directly pouring on the plants.. Like 8-9am or so. Early morning sun is not strong enough to burn the leaves ( the drops act as a lens, and focus the heat of the sunlight, leaving burn marks - Lights do the same thing ).


INFO on SOYANARA:

www.supernaturalbrand.com

according to the bottle.

Milk/water makes the whole room smell like puke. Buds too....

Too bad BIO SOY M (for mildew) is off the market, it worked the best. SOYANARA is their replacement. It also staves off Spider Mites, but I believe the products were better when they were specific (There was a BIO SOY I, and BIO SOY M - 'I' for insects, as well, but no longer), but still effective.

Best is to assume you have it, and spray preventatively with something organic. Then you won;t get it.


Rotsa Ruck, Y'all.

 

[Guest]

oh yeah, sorry to double post... But important:

Nothing really works without a good wetting solution....

I use Dutch Masters Penetrator in conjunction with all sprays, even though it is not organic.... !

 

[stinkyattic]

Lol this thread is deja vu, eh?
Neem oil. Weekly LIGHT mist. Don't overdo it. Never apply neem to the point of runoff. If the leaves have a slightly glossy appearance, you've got adequate neem.
Lower RH in flower. The same conditions that allow PM to thrive will also encourage other types of mold.

 

[nowlege]

Great info!

 

[The_Leader]

hey stinky and pharma is cannabis forums shut down? tripped seeing you 2 here.

icy..spraying and leaving lites off is who i grow shroos...and if water droplets burnt plants? how would plants grow outside...i mean sheesh...oh and we cropdusted w/ddt in the heat of the day ijm ga fla...nothing burnt up.

pharma w/pure cinnomon oil is suppose to help PM, but correct temps, RH, and maintenance PM will not grow.

 

[stinkyattic]

Naw, it's still up and running. Just spreadin' the love! ")

Damn, I didn't know DDT was still being used. Scary shit.

Water droplets can focus light like a magnifying glass and scorch little pinpoint spots on your leaves. It's rarely a problem indoors, but not unheard-of. Try not to spray in intense light, and use a spreader/sticker (surfactant) to keep the surface tension from making droplets.

 

[The_Leader]

ddt was in 7Os....Im old.

all my yrs growing on the farm. then weed outdoors and now indoors for 15yrs, never seen this lite burn. lucky i guess.

Ive not had any mold since controling all aspects of the grow 24/7. moisture is the food. take it away and no mold.

 

[PharmaCan]

Lol this thread is deja vu, eh?

Hey Stinky - I didn't know you speak Canadian. Deja Vu, yeah. I'm starting two scrogs with my MxB strain and I know I'm going to be fighting PM all the way just because this strain attracts it. With the scrog, it will be difficult to get anything to coat all the leaves because of the way the branches are tied. So I'm searching for suggestions. What's the brand name of a good surfactant?

Icysurfer - What have you found to be a good RH (indoor grows) to keep the PM at bay? Penetrator is supposed to make things absorb into the leaves better. I wouldn't want Penetrator with something like neem oil, would I? I mean, I've got Penetrator, I can use it, but do I want neem oil absorbed into my leaves?

PC

 

[Guest]

You can always use PENETRATOR at half strength.

I never use it at the level they list on the label. (60ml/l..!)

Neem is really better for insect pests. I would venture that if one is using Neem for PM, it is working because other conditions in the facility are also good.

I like to keep the RH at 45 or lower during the 'night,' and I usually do not even worry about it in the 'daytime,' except NOW, the rainy season, when I also try to keep it around 40-50% with the lights on. Too low, and the nugs are not really juicy, unless you get lucky..

I don't know about nature, I am a surfer, grower, not really a meteorologist, but my best instinctual guess is that it usually does not rain during the high sun periods...(?)

Water drops indoors definitely act as lenses, leaving burn spots. Later this plant will be more prone to diseases, like PM... And the circle is spinning anew.. lol

I just know that I never spray in direct sunlight, after about 930 or so.

It is not me who is the Big Brain... lol

I learn from the masters. Readijng their books allows one to pick and choose from the best disciplines known to cannabis growers collectively (because these guys published books, and others did not) - Soma, J. Cervantes, DJ Short, ED, Eddy, and all the rest.

If anyone needs any info during a power outage, make sure to have Jorge's 'bible' nearby.... I read these books while I eat - amazing what one can retain, when one is reading about something they love....!

happy New year, y'all... Live long and prosper..... Much success