[Grassachusetts7]

Oh the lovely Botrytis poked it's ugly head into one of my flowering tents. I'm so pissed, I'm just over a week from harvest and it struck one of my 3 plants in that tent. I chopped and hung the infected plant yesterday. I have it hanging in 50ish rh closet, so continued growth should not happen.
My question is the other 2 plants that shared the tent. No visible sings of rot but I'm extremely nervous, it's well over a half pound of med. I started my flush Sat. I grow in coco Hempy 5 Gal with Kiss feeding reg. I hate to prematurely chop these. Never dealt with rot before on an indoor grow. Right now in Mass it's 75-80% humidity out! My dehumidifier is working overtime.
Damn man, any support would be greatly appreciated!!
Thanks,
Grass

[Muss]

I got a product called nova 40, I had a huge pm issue for a couple years and then I got this product,it's been two years since my first and only application.
It's something I would only use in veg never on flowers.
If you don't ever wan to see mould again this product works, it's systemic and actually kills pm and keeps It away,I'm surprised there is so much pm issues on here with products like this out there.

[Babbabud]

a quick google search tells us nova 40 has the same active ingredient as eagle 20.
myclobutanil
nothing im gonna use on my smoke

[Muss]

Nova 40 saved my moms and it's a great thing to use one application and never see pm again.

[VenturaHwy]

OK I've read through a few of these threads on PM. Most people believe low humidity keeps PM from becoming a problem. But one person said he got PM at 25% humidity. So I am try ing to figure that one out.

The first time I had a real problem with PM was this summer. One plant was slightly infected a few years back but I lowered the humidity and kept it in check. So maybe one slightly infected plant in many years of growing….. until this summer. It was record breaking hot in the Seattle area here. I resisted buying an AC unit and it got so hot I had to turn off my dehumidifier. The air intake was from the hot garage maybe 100 degrees F into the cooler flower room of say 80 degrees F.

The hot air entering a cooler room could form moisture on the plants and cause PM to grow if present in the room.

But my question is why would it affect rooms with low humidity?

So maybe cool the hot outside air and dehumidify it before it enters the grow room?

[VenturaHwy]

Here is a UV light meant to kill PM -

"The CleanLight method is a fine tuned version of UVC specific for the surface of plants and the air in your grow room."
https://stoppowderymildew.com


And here is a study from Cornell that is interesting.

effect of light on powdery mildew
https://www.news.cornell.edu/stories/...cumber-disease

[coldcanna]

Stagnant air has been the root of PM in my experience. Plenty of people run high RH rooms you just have to have ample air movement, the more fans the better!

[VenturaHwy]

Thanks coldcanna, I have 2 fans in the room but more might help. I am starting to think there are some strains of this that are like the plague. I have looked at sulfur burners but I need one for small rooms, they make them for 1,000 sq/ft. I tried the Green Cure (potassium bicarbonate mostly) it seems to help so maybe just need to use a few more times . I wonder if anyone has tried a fogger that kills PM?

[the gnome]

Originally Posted by coldcanna

Stagnant air has been the root of PM in my experience. Plenty of people run high RH rooms you just have to have ample air movement, the more fans the better!

Ive had PM once in 4yrs
1st time i didn't run a fan because it broke
it was winter, my Rh is low this time of year and i didn't think twice about it until I was mid-bloom and though i was getting weird shadows across the leaves.
Volck oil did an impressive job of controlling it til harvest.
i picked a lot of the infected leaves and carefully treated the where the PM was the worst.
btw it took hold on the bottom 1/2 of the plants.
i got lazy and complacent and didn't lollipop and no fan.

btw Volck oil is great old school stuff, it's mineral oil,
it has a very low order of toxicity
kills mites, white flies, rusts and scale and many other critters
plus it's an ovacide

[VenturaHwy]

krunchbubble's thread on powdery mildew. Might only want to use this on a small clone and turn the clone into a mother plant 2 or 3 months later, to be safe.

https://www.icmag.com/ic/showthread.php?t=161425