Powder mildew... Can't catch a break lately

As you can see in the title. I've stumbled on some powder mildew. Right now my plants are a couple weeks into flowering outdoors. Couple of indica dom. Hybrids as well as some sativa. So some plants should be done right around October. Others will need longer and may come down a little bit early. The pm was found on a small plant which is chopped right away. Has maybe 5 or 10 leaves with a very slight appearance of pm. No big noticeable leaves destroyed though. I looked oved all my big girls and found only a handful of leaves on a few of them. I know some will say it won't be smokable or to just kill them but I've got 6 months into these plants and they should yield me anywhere from 5-10lbs.

So my plan is to treat the powder mildew as needed and try to keep to a minimum so that it does not invade its way into buds and stays on fan leaves.

1. What is the best way to treat these while in flower? I've read up on green cure as well as a few others but would like some opinions on best plan of attack throughout flower/ over the next month.

2. How fast does powder mildew travel through a crop? My plants are a good 5x5 each and are about 7 to 8 feet tall.

3. Is it possible to keep the pm to a minimum with there being only one month left in the crop? Well aware I may not see the harvest I planned for and May have to use some buds for something else but hoping to be able to save at least half of them.

Thanks for any help. Sucks to see pm invade what has been a great grow.

best way to 'treat in flower'? Cut off the buds that are infected and bin them, keep a close eye on nearby buds that were in the infection areas. Use a silica product along with seaweed extract on your next run to help prevent it.

Very easy to control through harvest but you'll have to keep spraying. Green Cure is great stuff, just a ph shock so fine for flower. Diluted H2o2 also works well in flower. I'd rotate back and forth between them and then get some Actinovate going when they look clean to act as a defense. Every time you see some pm, plan on spraying for another few days.

I saw it on Pbs so Google milk for powdery mildew. It's not for mold or bud rot but specific to pm good luck

sulfur burn is only control measure followed by sanitation. if you can't do that lactobacillus spray 3 times a week works better than h2o2, milk or Potassium bicarbonate. green cure is Potassium bicarbonate based, i haven't tried it but i used Potassium bicarbonate which burns the plants easily and is not totally effective. Potassium bicarbonate is a third choice. the rest are a waste unless you have no other option. neem may help prevent or not but doesn't work to treat it. a drop of dish soap and a dab of cooking oil in water is a treatment but not great. i hear eagle 20 is good if you want to poison the consumer of the weed. if you cut off the heavily infected it will help somewhat.

cure your bud fast as it can spread after harvest. some strains are more effected after harvest.

ANC said:

http://www.tandfonline.com/doi/abs/10.1080/07060669809500391

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interesting, you try it?... wait a sec, plus fungicide...
Foliar applications of 1% solution of mono-potassium phosphae (MKP = KH2P04) fertilizer plus Triton X-100 (0.025%), sterol inhibiting (SI) fungicides, and an alternating treatment of phosphate fertilizer and SI fungicides inhibited development of the powdery mildew fungus Sphaerotheca pannosa on fruits and leaves of nectarine trees

I thought the emphasis on the 1% MPK administration was more obvious than what it was. I was suggesting you try that with whatever you are dosing to correct your problem.
I have never had PM problems. Proper preparation and all that shit.

Yea the last month of flower is the worst for PM, the plants immune system shuts down and she is wide open for attack. Unfortunately most treatments that get rid of the spots (green cure, h2o2, actinovate) are applied thru foliar spray, which creates the ideal conditions for a rebound attack. The spores land on the leaf surface and send out tendrils looking for water in the channels within the leaf structure.

Your best chance IMO would be a cleaning spray with something like green cure, which should work fairly quickly, then follow up with a protectant like Neem oil which should help create a barrier the spores will have to fight through.

Also try using a Calcium paired with L-Aminos to give the plant help defending itself, it's said to increase the pectin in the water channels in the leaf, making it less palatable for the PM spores.

ANC said:

I thought the emphasis on the 1% MPK administration was more obvious than what it was. I was suggesting you try that with whatever you are dosing to correct your problem.
I have never had PM problems. Proper preparation and all that shit.

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i got that but it said it worked with specific fungicide. any thing else would be an experiment. maybe a lead but not an answer. i didn't mean to be so dismissive. i just posted the answer and i know from experience and research. also lucky you.

silica and a healthy plant also help prevent and defend.

GuyLeDuche said:

Yea the last month of flower is the worst for PM, the plants immune system shuts down and she is wide open for attack. Unfortunately most treatments that get rid of the spots (green cure, h2o2, actinovate) are applied thru foliar spray, which creates the ideal conditions for a rebound attack. The spores land on the leaf surface and send out tendrils looking for water in the channels within the leaf structure.

Your best chance IMO would be a cleaning spray with something like green cure, which should work fairly quickly, then follow up with a protectant like Neem oil which should help create a barrier the spores will have to fight through.

Also try using a Calcium paired with L-Aminos to give the plant help defending itself, it's said to increase the pectin in the water channels in the leaf, making it less palatable for the PM spores.

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the advantages of lactobacillus are better coverage and an active shield that lasts over 24 hours where as with k bicarb the effects last only till the plant drys , it kills but not all of it and it's more work for less reward than lactobacillus. sulfur burn always works. i have read and tested almost everything and all treatments are lacking

Thank you all for the replies. Much appreciated.

Bugeye said:

Very easy to control through harvest but you'll have to keep spraying. Green Cure is great stuff, just a ph shock so fine for flower. Diluted H2o2 also works well in flower. I'd rotate back and forth between them and then get some Actinovate going when they look clean to act as a defense. Every time you see some pm, plan on spraying for another few days.

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Thanks for the advice. I ended up getting some green cure and have used twice so far. Once on 9/5 and again on 9/11. Unfortunatly it did burn the tips of my pistils on a couple of plants. However I consider that a small sacrifice if I'm able to keep the pm to a minimum for another 3 weeks. Hoping they will all be done or pretty Damn close to done by October 1st. October 7th the latest. Since spraying I have found a few leaves here and there that have a little pm. But as for the big plants I've only been seeing it on 2 of them. Just started moving toward the tops of the plants so I'm trying to keep it low somehow.

esh dov ets said:

cure your bud fast as it can spread after harvest. some strains are more effected after harvest.

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That is interesting. I did not know that. I did watch a video from jorge Cervantes where he had mentioned washing buds come harvest time if you had pm. Using a couple buckets with plain wAter and a bucket with h202 mix. So I am going to do that as well and def do a little research on the pm spreading after harvest. Thanks man

GuyLeDuche said:

Yea the last month of flower is the worst for PM, the plants immune system shuts down and she is wide open for attack. Unfortunately most treatments that get rid of the spots (green cure, h2o2, actinovate) are applied thru foliar spray, which creates the ideal conditions for a rebound attack. The spores land on the leaf surface and send out tendrils looking for water in the channels within the leaf structure.

Your best chance IMO would be a cleaning spray with something like green cure, which should work fairly quickly, then follow up with a protectant like Neem oil which should help create a barrier the spores will have to fight through.

Also try using a Calcium paired with L-Aminos to give the plant help defending itself, it's said to increase the pectin in the water channels in the leaf, making it less palatable for the PM spores.

Click to expand...

Thanks man. As I mentioned above I ended up getting the green cure. I will look into those calcium and l aminos to get thru these next couple weeks though. Going to be a looong few weeks haha