White Powdery Mildew Solutions?

[Jhodg2787]

Hey All,

Started noticing some white powdery mildew on my plants the other day and im kinda looking to see what the recommendations are on removing the mildew as well as ways to prevent it from continuing to spread. Everything I've read says neem oil and/or hydrogen peroxide should do the trick... but im wondering if the are any soil additives I should be using. All 6 if the plants im growing (2x MOB Berry, 2x Durban Poison, 2x Jack Herrer) have small amounts of spots that I attempted to wash off with tap water yesterday, also checked the humidity in my tent and it was at 42%. I'm currently running only one 6"fan in the tent with both an inline fan fire air in and a carbon diffuser for my air output fan. Any insights would be great though as I'd like to prevent the mold from spreading onto the buds during their bloom phase.

-J

 

[Mr.furley]

Don't use neem oil on flowering plant as cannabinoid bind to oil. A dilution of h202 and water to wipe the WPM off the leaf is a good start, next I would remove some leaves and make sure you have good airflow and ventilation. After your Harvest clean all of you grow equipment with a bleach solution 100 parts per million in water to mitigate any future problems.

 

[Smokesteve]

I use this it's safe up to cut down day. https://www.amazon.com/Fungicide-Proprietary-Powerful-Geraniol-Ingredients/dp/B01J1QU65M

 

[Jhodg2787]

So if I have already hit them with neem once, obviously don't do it again, but my next question is with regards to defoliation of the plants. I've honestly never done this, so in wondering how I go about doing that to decrease leaves touching one another, etc.

 

[Mr.furley]

Take 25% of you biggest fan leaves to start with. Starting with one of the two that are touch, stand over the plant if you can and focus on the middle. Remember you can always take more later but can put them back.

 

[Jhodg2787]

Alright, makes sense. Unfortunately going to have to wait until Sunday to defoliation because we also have to dedicate significant time to tying them up also to keep them from dropping. We added two more fans to the tent today making it 3 oscillating fans total with two running air across the top and one circulating air on the bottom. I'll keep you updated. Thanks again.

 

[Cali]

I would go with mr. Furley recommendations too late for neem oil. Best bet would be to wipe the leafs with hydrogen peroxide or some arm and hammer or whatever brand you like of bicarbonate dilute a tea spoon in water and wipe don’t spray since you already have buds growing. But next grow just do a treatment of neem once a week and forget about any issues. Neemresource.com highest quality neem and Karanja which are almost the same

 

[Smokesteve]

I respectfully disagree. The answer is in the link I posted.

 

[homegrown]

Hey Smokesteve, just checked the link cause im always looking for something better..Ahhh im not spraying that on my buds. I went and checked the Laboratory Chemical Safety Summary(LCSS) and it says Geranoil 106-24-1 is corrosive as well as a skin/eye irritant. I didnt even read on to see what happens when you burn it.. Cant get it in Canada..thats what got my attention. And at 26$ for 2oz thats pretty rich for me..lol

 

[johnb1963]

hello, i had WPM issues this past summer on my outdoor grow. what worked best for me was milk/water mixture, 30/70. let the mixture sit in the sun for one hour before spraying.

 

[Jhodg2787]

Serious question regarding my WPM issue. After having gone in and thought I had the situation at bay it still appears to be cropping up. We've got about 3-4 weeks left until harvest and im wondering what the thoughts are on spraying hydrogen peroxide and/or some other form of fungicide such as green cure or actinovate?

 

[Mr.furley]

I would suggest to wet a rag and wipe vs. Spray. Try to keep it off your buds.

 

[Jhodg2787]

How do you feel about me taking all of the plants out of the tent and then doing a deep clean of the tent with hydrogen peroxide solution as well? Im looking at needing to keep these plants as issue free as possible for the next 3-weeks until they are all done blooming.

 

[Mr.furley]

Yes. Wipe as much down without getting it on your buds.

 

[Jhodg2787]

Okay, wiped down the tent, performed more defoliation, and cleaned many of the affected leaves. Ensured the air purifier I'm using had a new filter, and have now noticed a new problem. Phosphorus deficiency... any ideas on something I could use as a top dresser or mix into my soil at this stage about 3.5/4 weeks into flowering?

 

[Mr.furley]

Can you throw up some new pictures in nature light since its been a minute.

 

[Jhodg2787]

Sure thing I've circled the suspects in red

 

[Jhodg2787]

Updated photos (almost 4 weeks into flowering)

 

[Jhodg2787]

The photos are at the bottom of this thread

 

[Mr.furley]

Do you got a good pocket microscope or Loupe?