Can't solve Powdery Mildew after week 4 of bloom. Need advice

Hey folks.

Powdery mildew is my nemesis. No matter what I do every plant eventually gets infected. I've come to realize it's just a given in my environment.

Now, I've been able to control it quite well by keeping up with weekly or bi-weekly foliar sprays of the following concoction:

1 Gallon of Water
2 Tbsp of Neem Oil
2 Tbsp of SM-90

This works quite well until about week 4. Beyond 4 weeks of bloom I am stumped as to what I can do in order to keep the PM from attacking my entire crop, as I don't want to apply any more neem or anything else that could effect the taste and quality of my meds.

Due to my health problems, I am looking for organic remedies only. I will not apply anything like Eagle One or whatever that carcinogenic systemic treatment is called.

I have used green cure to save my crops before, but it only really works at the highest label dosage, and at this level it burns the shit out of my pistils and makes my buds look terrible. Rather not use this until the last week before harvest as a last resort once the pistils have already died back and turned orange.

Foliar sprays of hydrogen peroxide at 3% and 7% hasn't been much use as it doesn't seem to even contact the powdery mildew when I spray it - it just beads off. Maybe I need to add something like a spreader sticker but I'm not sure what to use and at what doseage.

And the last thing I've tried is spraying alkaline water at a ph of 8-9, but again, it just seems to bead off the plant. Again, maybe I just need to use a spreader sticker of some kind, but I'm not sure how that would effect the ph.

Sulfur burner is out of the question as, in my opinion, it completely ruins the taste of my buds.

So that's what I've attempted thus far. I know environmental controls and stopping PM before it even gets started is key, but I just have to assume it's here to stay because I have my temps, humidity, air circulation and everything in check and it still comes back.

So that's my predicament. Any advice on how I can keep PM subdued through the last half of flowering? Keeping in mind I will only use natural and organic means.

Thanks folks, really need some help on this one.

I use 1 part skim milk 3 parts water, couple of drops of dish soap. It doesn't cure it but it will clear it up for about a week to 10 days. Works every time. I do it with lights on.

Doesn't it end up smelling like sour milk after an application or two? I would imagine the heat with the milk would end up smelling rotten pretty quickly.

Whats yor RH?

between 45 and 55%, but it drops as low as 30 between waterings

Milk and water should be all you need.

http://www.gardenguides.com/779-using-milk-control-powdery-mildew-garden-pest-tip.html

It doesn't smell if you use skim milk.

if you don't want to use anything that works then you need to fix your enviroment. period

good luck PM is a room killer

i had exact same problem recently mate in week 4, i couldnt get rid of it just kept it under control and off the flowers best i could. Remove any badly effected leaves carefully so you dont spread it, i used baking soda and water or any alkaline water will work. I just gave them a good misting then turned fans on them till dry. Any more that would appear i applied the soda water just to the effected area and wiped with wet fingers till clean. Im smoking my harvest now and its mint just be careful during drying aswell, smell them regularly and remove anything suspicious looking asap.
Worked for me so i hope you have the same luck its nasty stuff

add a 1/2 cup 3% h202 to a 32 oz spray bottle water and some spreader....spray your plant every 3-4 days til harvest

Get yourself a hoselock water butt pump or similar and decent fitting to create a shower. The pump will give you fantastic pressure to use H202. It will use alot of water but you can recycle. Secondly, lollipop ya plants and get some good air circulation going down below.

Less plants, how many you got in what size space.

All i can say is the milk method worked well for me. It held it off until harvest. I sprayed two days before harvest then i did this

haven't tried it but one product made for this is a PM Wash by NPK Industries (the makers of the excellent mite killing spray Mighty Wash ).

i can attest to the milk/water combo (although i do 1 part skim to 10 parts water) - you can also use whey (closest everyday source would be the watery stuff you find on top of yoghurt). i've never noticed a rotten milk smell, and i've been using it since around '01 when i was first given the tip. wine business monthly claims whey + water was just as effective as a sulfur spray on chardonnay plants (notorious for PM issues). i have the article bookmarked somewhere, i'll try to dig it up.

do you bleach/h202 your room between shows? it helps. hepa filter on the intake might help somewhat too, depending on your outside environment (but if you have any big leaf maples nearby, yer gettin' it).

also: i haven't used it, but there's an OMRI certified fungicide called 'actinovate' -- i got some literature for it at the agriculture show but have no idea whether it actually works or not.

new product from liquid ladybug, for p.m

http://powderymildewremover.com/buy-now/

I'm a hydro grower, so I don't know how well my information would carry over to a soil grow, but this is my approach to PM.

Instead of viewing it from the remedial angle after it has already manifested on the exterior of your plant, I think of it as an internal problem waiting for the right external conditions it needs to thrive. So I simply deny it the exeternal conditions it needs to live... nipping the problem in the bud. How? By sterilizing my res/root zone with horticultural grade h202. Maintaining a more alkaline PH and regular treatments of H202 are the best lines of proactive defense.

If there is a way to sterilize soil, I would look into that. Your whole grow area, too.

Are all of your plants the same strain? I had a pm issue with one strain while the other five were fine (in the same environment). Perhaps try a different strain next time; after cleaning the room.

I run perpetually, but I pull everything out every 12 weeks and bleach it down good. It really doesn't seem to make a difference.

I tried the milk spray tonight just before lights out so we'll see how things go over the next few days.

Is spraying once a week enough, or will I need to spray more frequently?

every 3-4 days with deluted milk or h202

You dont want to spray just right before your lights go out that will promote bud rot...

I live in the PNW....Cant get rid of PM but I can keep it to a minimum