Powdery Mildw, early flowering!

[greenops]

So finally I got my scrog full of bud sites, thinking all my time and hard work is gonna pay off big time.. but now this thing!

Yesterday (3rd week flowering) I noticed several leaves on the edge of the scrog with this powdery substance. After closer inspection I noticed that 3 out of 6 plants are infected with PM.

So I googled all day long to learn more about this.

And here is my first question, some people are saying they will never smoke buds from a plant that had mildew, on the other hand I've read posts saying PM isn't even "that big of a deal"... What can you guys say about this? I don't like the idea of growing weed just to process it into edibles or hash, so if this isn't even worth fighting for, i might just stop it now.

Ok, so I've learned about milk, baking soda and burning sulfur. Since i've read negative experiences with spraying milk and baking soda, i went to my local grow shop to check if they have sulfur. What they had was sulfur in powder form. 1g has to be mixed with 1l water, then spray it all over the plant.

Anyone else had experience with spraying sulfur?

I'm also open for any kinds of tips... Thanks!


ps. Oh yea I wanted to add that the humidity is already low at 25% to 40% max, due to the climate outside.. Temps are within normal range.

 

[greenops]

bump... please.

Primarily I need to know, if I can still smoke the buds as long as I can manage to limit the spread of the PM and stays away from the buds?

 

[pip313]

Good luck limiting it,try the sulfur or do what I do and pull every infected leaf for the next week. If your pulling a handful every day cause its spreading then consider scraping them.

No strain of pm and there is a bunch is toxic. Again not toxic. That said its mold.

Some say pm is in the plant and that's that. I've took a small clone and removed infected tissue then veged for 10 weeks and got over a pound no pm. Wasn't the best documented thread

https://www.icmag.com/ic/showthread.php?t=248351

 

[SpareRow640]

I would not try to pull every infected leaf for a week unless it is a last resort, that usually results in a bunch of bare stalks as you proceed to pick every newly infected leaf and sprinkle some spores over the rest.

The sulfur sprays are effective, but a room that size only in week 3, a burner might be worth ordering.

There is an organic, systemic fungicide - Exel LG. Safe, effective, even gives a little P/K to the leaf.

Option 3- fungal dominant compost tea, Capulator makes a good one. Load that phyllosphere with so much beneficial fungus there leaves no room for PM!

 

[mack 10]

green cure?

 

[the gnome]

I'd hit it w/greencure
with some H2o2 added to it.
worked for me, but since PM is systemic once it takes hold you'll have to reapply it to keep it down

 

[the gnome]

green cure?

here's something from when i had it in late bloom
for some reason it doesn't want to C+P??
heres a link to the thread
https://www.icmag.com/ic/showthread.php?t=253289

use the greencure-3 small scoops mixed with 1/3 cup h202 in a 32oz spray bottle water... spray all your plants...your grow area needs a cleaning too...easiest way get a antifungal bomb...Fungaflor

[FONT=Arial, Helvetica, sans-serif][FONT=Arial, Helvetica, sans-serif]Dr. Horst’s research validated the power of Potassium Bicarbonate as an effective way to kill mold spores and prevent them from taking root. GreenCure® uses several modes of action against mildew the most obvious of which is that it causes spores and tubes to suffer immediate and rapid water loss, thereby effectively killing the fungus. Once destroyed, the residual spore material often sloughs off or washes away.

GreenCure’s® effectiveness can be viewed under an Electron Microscope (pictured on below), where it is possible to see how the mildew spores on the right are completely withered after being treated with GreenCure®. The spore on the left is untreated and remains plump and continues to send out an infectious tube to spread its destruction
[/FONT]

kills anything it gets in contact with

but

pm will always return because its systemic...reapplication to infected plants is a must once a week [/FONT]

 

[talktosamson]

Greencure once a week until its gone. It's organic and it takes care of business!!

 

[old grunt]

A few years my plants got P.M. and I sprayed them every other day with hydrogen peroxide 0.3% for about 3 weeks and they all turned out just fine.

 

[Gr33nman]

actinovate, or greencure, or zone and penetrator by dutchmasters, or sulpher burner, for early flower, .....but , eagle 20 for veg and boom. done

 

[Gr33nman]

peroxide uhh? gonna try that one day

 

[old grunt]

Gr33nman give it a try,it won't hurt your plants at all. And for this sixty plus year old stoner vet. it was kinda fun watching the P.M. turn into snot, die and fall off my plants.Also I still have 2 qts. each of Ducthmaster zone and penetrator unopened in my basement, by the time u.p.s. delivered them I had the P.M. pretty much under control using hydrogen peroxide .3% .

 

[DeoXy]

+ 1 for green cure.. just a note : use slightly less than directed as it can cause *some* pistil withering/brown @ full strength.

 

[greenops]

thanks for your tips guys. the thing is green cure isn't available around here.
I hope I can get some hydrogen peroxide at the pharmacy.

Old grunt, could you explain how to use it? Do i have to dilute it in water or just spray as is?

 

[old grunt]

Just Spray as is and where the P.M. is thick adjust your sprayer to almost water pistol setting and shoot the bastard,one or two shots will turn it into snot right before your eyes,where it's not thick just mist.

 

[greenops]

ive heard from someone else that hes applying hydro perox only during lights out because otherwise it can burn the plants. i would have a problem with that because i'm not around during lights out plus i dont have special lights that can work during those hours. so can u also use it when lights come on? do u spray on buds as well?

 

[FlamingFlowers]

Oxidate gets it on contact.
Watch it with the eagle 20. That is some scary stuff. Endocrine interrupter and has a booklet for a warning label. The Gov knows it could be used by enviro terrorism. I wouldn't go near it ever again.

 

[stasis]

I have been asked about PM so many times. Thought I'd volunteer some info based
on my growing within 3 miles of the Pacific for years. PM has always been an
immense challenge for me. This is what I found. Random and not techniques for
dealing with this scourge.

Remove all leaves 50% or more infected. But
do not defoliate entirely.

Remove all foliage 1/3 of the way up the
plants to insure airflow.

Any plants that are exhibiting PM on the stem
in a big way, remove from room.

Spray "SAFER Garden Fungicide," The
Concentrate if you can find it - mixed at 20-25ml/g, with just a few drops
of coco-wet or another spreader/sticker.

No adjustment to lower the
water pH wise, but test it. Make sure it is 7.0-7.5 pH with the sulphur in
there. High pH retards the growth of the Fungus. That is why baking soda helps
(not good enough to save you though).

DO NOT SPRAY THE HAIRS (pistils). They will burn and turn brown prematurely. Lowering the value of your hard work.

If you are up to the 3rd week of flowering, you are only going to get one maybe two shots at this.

If necessary, due to a sloppy sprayer mechanism, hold a piece of cardboard or a
playing card blocking the flowers as you spray. Spray spots, not necessarily the
whole plant - unless in veg, or 1st week of flower. Shake the water every couple
minutes as you spray. Don't get the sulphur spray in your eyes, it feels bad.

Turn off all fans before spraying to avoid a mistake like this (from
experience. Ouch).

Wear a mask of some sort. Protective glasses.
Long-sleeves. Wash hands after finishing., wash clothes, maybe take a shower.
The Sulphur won't kill you, but it is nasty.

A sulphur burner is great,
but unsafe, as they are made. There is no temperature regulator. The 'pan' sits
over the heating element and the up and down is adjustable. Make sure it is
tight, and the pan is sitting at least 1 inch above the element. After the
safety of the heating element is established the pan can be moved down to 1/2
inch above the heating element. Again you do not want the element to be touching
the pan. Heated Sulphur is terribly dangerous. I could see something awful
happening in a spill. If You hang it high, it is very dangerous to turn off.
Only pulling the plug turns it off. There is no switch Usually. Not only is the
S molten, but caustic as all hell. I cannot even imagine what molten sulphur
would do to someone's arm, or worse. Warn your people about the sulphur burner
please if you use one.

To operate, Burn sulphur "Prills" for up to 3
hours, but 1.5 is what I usually do in an indoor room. I do it in the dark
period (18/6 for veg, 12/12 for flower of course) right when the lights go off.


For safety, in case I pull a Stoner-manoever, and forget to turn the
thing off, I put it on a timer. Since it will take time to heat up, and take
time to cool down, the room gets about 2 hours with the carryover heat after I
turn it off continuing for a half an hour or so 'til the pan cools entirely. The
Sulphur will turn solid after cooling. Do not touch the Burner or try to empty
it until then. ESPECIALLY if the Prills got very very hot and turnef into a
clear, crimson oily substance. Molten Brimstone, folks. DANGER, WILL
ROBINSON.

If in a house, make sure to vent.. Keep pets out and away. They
don't always realize just because something smells bad it is bad.

Either
Spray, or "Sulphur burn" once a week or every 8 days, if you can wait. Then, You mustn't spray anymore
after 4 weeks or so into flower. Especially spraying in the room. This after a certain point asks for Botrytis,
(Bud rot), and the moisture encourages the PM you are trying to eradicate.

PM (and its' Cousin Downy Mildew) is systemic, like in the Blood, and all you can do is buy time for
the plants to finish.

Using either method of Sulphur distribution as a preventative is not a bad
idea.

IMO, Burners are better for greenhouses, and for an extra
protection maybe in week 4 of flower. Sprayable Sulphur is maybe better for
indoor. Less noxious.

I do not like the way Sulphur Burners stink up the house. I am sure it is not healthy to breathe.
Once, before I used a timer, the thing went for about 4 hours. My Breathing within the house was affected.

Keep PPM's down. Especially N is
attractive to PM.

Do not water too frequently, or too much per watering, but water almost fully. Overwatering is the biggest and most frequent mistake. Give your plants love, let the roots get some O2 airflow. They cannot get oxygen if they are always wet. Marijuana likes to have it's soil dry out a bit. Not to let the plant wilt, but just before that. Growth of MJ is enhanced by not overwatering. Mildew can increase from excess moisture in the air, and also if the roots dry out too muc, It is a delicate balance.

In a Hydroponic or certainly an Aeroponic situation it is almost impossible to overwater.

Always water container Soil (such as Potting mix, or a Fox Farm Product i.e.) or Soiless Medium (Promix, Sunshine Mix) at the beginning of a light cycle, not within 6 hours of the lights going off, at the latest. Try for the first two hours of light.

Outdoors, in containers, try to water after the sun comes up and starts to get warm, but not after 11am or so. Lets the container soil dry out a bit before sundown (or lights-off indoors) when the Humidity goes high.

Make sure the "temperature differential" (hottest to coldest) of the room is no more
than 15 degrees. Shoot for 10. A differential over 15 degrees encourages PM.

If it's cold indoors perhaps a garage, or shed, or even in a Greenhouse, use a heater at night on a timer to keep the differential down. I like the Oil-filled electric heater for safety. One of these set on the 1st setting, but at full will use as much power as a 400W light.

Cool (night) temps encourage the fungus. Especially important in greenhouses that seem to collect
condensation at night. Keep it warm with that heater and a fan lightly blowing through it, to distribute the little heat.

Make the heater(s) go off while the lights are on,
or during daylight in that greenhouse.

That will all keep the temperature differential
down as well as keep the room dryer.

Use a dehumidifier, indoors set at 50%.
Keep at max 60 in veg, and 55 in flower. Remember the Dehu adds heat to the room.

Keep air moving. But not directly
on the plants. In a complete infestation at the end of a crop - turn the fans down, as
they distribute the fungus.

PM is ubiquitous. It is everywhere outside. Certain
plants/strains are more susceptible to PM than others. OG Kushes, for example
are often a magnet for PM. Weakened or overfed plants seem to suck it out of the
air too.

It is not good to smoke Powdery Mildew infected bud. Keep the PM
out of the bud, and that can be acceptable. Some make hash out of it, not me.

Good Luck.

 

[greenops]

Thanks for your elaborate post Stasis!

Were u referring to Safer Garden when u said:

DO NOT SPRAY THE HAIRS (pistils). They will burn and turn brown prematurely. Lowering the value of your hard work.

If you are up to the 3rd week of flowering, you are only going to get one maybe two shots at this. ??

Because later on you said I can sulfur spray once a week? So I'm not sure when to stop applying the sulfur spray.


I spoke to a guy working at a local hydro store. He advised against the use of sulfur burner as it wouldn't be as efficient in a smaller tent. He recommended that I should use another fungicide product that stops the spread and kills spores. So I'm looking at combining that product, with sulfur spray and hydro peroxide.

My question regarding hydro peroxide... can it be used during the light cycle? I was told to do it during lights out as it may burn the plant.

 

[Lapides]

JMS Stylet Oil.

I battled PM for a period longer than I like to think about. I tried all of the above suggestions. They all worked, temporarily. JMS Stylet Oil finally eradicated PM for good in my garden. It's organic, odorless, colorless, and I believe, tasteless. You can use it up to the day of harvest, even with cannabis. From what I read, the grape industry is using it more and more to battle their PM problems. It even kills spider mites. I have a HUGE jug on hand at all times now, just in case.