PWM on clones, Will i ever be able to eradicate it?

Cookoo4Coco · Apr 12, 2021

Hey! Got some clones about a month ago. They are growing pretty good other than some PW Mildew.
I didnt notice it at first and it spread really slowly for a sec i thought it was stressed and trying to flower/get frosty LOL
Last 2 weeks or so ive been spraying it with low dose H202 Spray and it goes away for a day or 2 then i stop spraying and it comes back!

My spray is approximately 380ml RO 1/2ml 38% 1/2ml Calmag

If spray that every other day the PWM doesn't re-appear then both times ive stopped spraying it comes back after a few days

Do i need to spray everyday? Should i switch to Neem or milk or something?
Not gonna move em into my clean tent until i know its totally gone.

Thanks!

Oldguy71 · Apr 13, 2021

Spray the entire plant with 1/2 tsp baking soda Into a 32oz water. One application should do it. Molds need an acidic environment to thrive.

KingTubby · Apr 13, 2021

Sounds like you need better air circulation, which is the main contributor to PM.

Cookoo4Coco · Apr 13, 2021

Oldguy71 said:
Spray the entire plant with 1/2 tsp baking soda Into a 32oz water.

Ill give that a try! hated the idea of getting milk or oil everywhere using the sprayer lol
obviously ill test a leaf or 2 first

KingTubby said:
Sounds like you need better air circulation, which is the main contributor to PM.

I dont think that is the issue, I got 3 Fans blowing on them and they are in an open room with fresh air being pulled through.
Thanks for the input though!

Found some chrysanthemum flowers 4 feet away from my entrance that were hit with PWM as well, and they were in the open air and in full sun!

Might just be a hazard of this new location. Might have to do some cleaning and weeding by my intake vents....

KingTubby · Apr 13, 2021

Cookoo4Coco said:
Ill give that a try! hated the idea of getting milk or oil everywhere using the sprayer lol
obviously ill test a leaf or 2 first

I dont think that is the issue, I got 3 Fans blowing on them and they are in an open room with fresh air being pulled through.
Thanks for the input though!

Found some chrysanthemum flowers 4 feet away from my entrance that were hit with PWM as well, and they were in the open air and in full sun!

Might just be a hazard of this new location. Might have to do some cleaning and weeding by my intake vents....

Direct exposure to PM is definitely going to be a prime concern, however the spread of PM is mostly environmental. Lack of airflow, low temps, and high humidity are all contributors. How low do your temps go overnight, and what is the rh?

Kanzeon · Apr 13, 2021

PM is systemic, it's like plant herpes. The clones and any plants grown from them will be susceptible to it.

I'd kill them, bleach everything, and start over. PM is no joke.

Anthem · Apr 13, 2021

If the PM grows into the plant, it will continue to come back. Once it gets into the plant it will not go away. looks like Kanzeon is well aware

Kanzeon · Apr 13, 2021

Anthem said:
If the PM grows into the plant, it will continue to come back. Once it gets into the plant it will not go away. looks like Kanzeon is well aware

I've fought that battle. Even if the genetics are some mad dank rare cuts like @kaka runs, it's not worth trying to fight it.

KingTubby · Apr 13, 2021

Kanzeon said:
PM is systemic, it's like plant herpes. The clones and any plants grown from them will be susceptible to it.

I'd kill them, bleach everything, and start over. PM is no joke.

PM is not systemic, that is a fallacy. People sometimes get confused because they might use a systemic such as Eagle20 to get rid of PM. However PM doesn't go into your plan in one spot and come out at a different spot, which is the definition of systemic. You can get rid of PM with the proper environmental controls. Sanitizing the grow area is a good idea too though.

KingTubby · Apr 13, 2021

Anthem said:
If the PM grows into the plant, it will continue to come back. Once it gets into the plant it will not go away. looks like Kanzeon is well aware

Kanzeon said:
I've fought that battle. Even if the genetics are some mad dank rare cuts like @kaka runs, it's not worth trying to fight it.

You guys didn't try hard enough. I've made it go away.

KingTubby · Apr 13, 2021

Powdery Mildew and Fungicides: Part 1: Background

Quest dives into the basics of powdery mildew and fungicides. Beyond that we'll look at steps to avoiding and treating this fungus.

www.questclimate.com

Kanzeon · Apr 13, 2021

Is Powdery Mildew Systemic?

Cannabis growers are divided when it comes to whether powdery mildew is systemic, but what does the science say?

www.medicinalgenomics.com

"In one camp, there are those who believe PM is a systemic pathogen that permeates via the plant’s vascular system. Others believe is it superficial pest that spreads across the plant’s surface?

It turns out, there is a good reason for the debate. Based on the available literature and the tests we have conducted at Medicinal Genomics, it’s not clear whether PM is systemic. The science is still out. "

Regardless of whether it's technically systemic or not, the fact remains that once PM is visible, the spores contaminate everything in the surrounding area. Just because a grower can't see PM doesn't mean it's gone. Sure, someone can try to eliminate every last spore in an area and baby infected plants and it's possible for things to get better.

But the amount of effort required is so much higher that just dropping new seeds in new dirt after cleaning the environment thoroughly is generally the most efficient move.

cottageman · Apr 13, 2021

PM is not systemic and you can definitely beat it but it’s not usually as easy as one spray and you’re good. The reason why people believe it’s systemic is because they will kill the visible spore on the leaf, but not the shoot(forgot what it’s actually called) that goes down into the plant to feed, but the pm doesn’t spread within a plant you you can completely eradicate it. Geraniol is excellent and killing both the spore and the shoot of pm, silica and beneficial microbes work wonders as well. I beat it in my room by using a combination of power si for silica and amino acids, and og Biowar foliar pack for one “beneficial” spray, and then I’d do another “kill” spray and rotate banish(concentrated geraniol) and something like plant therapy or purecrop1. I had pm in all my rooms in a 12 light grow and completely killed it

cottageman · Apr 13, 2021

cottageman said:
PM is not systemic and you can definitely beat it but it’s not usually as easy as one spray and you’re good. The reason why people believe it’s systemic is because they will kill the visible spore on the leaf, but not the shoot(forgot what it’s actually called) that goes down into the plant to feed, but the pm doesn’t spread within a plant you you can completely eradicate it. Geraniol is excellent and killing both the spore and the shoot of pm, silica and beneficial microbes work wonders as well. I beat it in my room by using a combination of power si for silica and amino acids, and og Biowar foliar pack for one “beneficial” spray, and then I’d do another “kill” spray and rotate banish(concentrated geraniol) and something like plant therapy or purecrop1. I had pm in all my rooms in a 12 light grow and completely killed it

Forgot to also mention foliar spraying calcium when your plants are growing the most also has a huge benefit to managing and resisting pm

KingTubby · Apr 13, 2021

Kanzeon said:
Is Powdery Mildew Systemic?

Cannabis growers are divided when it comes to whether powdery mildew is systemic, but what does the science say?

www.medicinalgenomics.com

"In one camp, there are those who believe PM is a systemic pathogen that permeates via the plant’s vascular system. Others believe is it superficial pest that spreads across the plant’s surface?

It turns out, there is a good reason for the debate. Based on the available literature and the tests we have conducted at Medicinal Genomics, it’s not clear whether PM is systemic. The science is still out. "

Regardless of whether it's technically systemic or not, the fact remains that once PM is visible, the spores contaminate everything in the surrounding area. Just because a grower can't see PM doesn't mean it's gone. Sure, someone can try to eliminate every last spore in an area and baby infected plants and it's possible for things to get better.

But the amount of effort required is so much higher that just dropping new seeds in new dirt after cleaning the environment thoroughly is generally the most efficient move.

I've had PM. I've gotten rid of PM. Haven't seen it in a long time.

Foliar sprays of potassium silicate will also help to prevent PM infection, because it helps to harden the plant cell walls, and also raises leaf surface ph to a place where PM can't survive. You can have a whole room of PM spores blowing around, but that doesn't necessarily mean that your plant will get infected. If you have healthy plants and proper environmental conditions, PM can't gain traction. Low nighttime temp swings below 60F, combined with high rh and poor air circulation are the leading causes of PM infection.

cottageman · Apr 13, 2021

The Connection Between Mildew and Calcium Nutrition in Agriculture

Helena Agri-Enterprises, LLC has grown to be one of the nation’s foremost agricultural and specialty formulators and distributors in the United States.

helenaagri.com

That’s a great article explaining the benefits of calcium in plants and how it helps prevent diseases like pm and Downey mildew

Wh1teScorp1on · Apr 13, 2021

Get pure crop 1. Solve all your problems at once organically. No I don’t work there but I’m a happy customer

Kanzeon · Apr 13, 2021

KingTubby said:
I've had PM. I've gotten rid of PM. Haven't seen it in a long time.

Great, me too. I never said that it's impossible to treat, just that the amount of effort required generally isn't worth it unless the genetics are really special.

Cookoo4Coco · Apr 13, 2021

KingTubby said:
Direct exposure to PM is definitely going to be a prime concern, however the spread of PM is mostly environmental. Lack of airflow, low temps, and high humidity are all contributors. How low do your temps go overnight, and what is the rh?

My temps overnight this time of year can drop to the low 50s, My RH is generally around 40-45%

It first appeared when i was watering some seeds with a mister next to them at night. Obvious no no as the mist was hitting them and was making them damp a couple hours B4 lights off

I think Step 1 is continually treat the plants. My guess is that my H202 spray is killing the "tops" but not the "roots" of the Mildew
So im going to do a baking soda test tomorrow morning
Step 2 will be clearing all the plants next to my intake vents vacuuming and wiping down the walls wherever i can reasonably reach
Step 3 will just be waiting a few weeks and seeing if its clear before i put em into the flower tent. Just gonna be a low and slow veg in the clone area i guess.

Also i think i will increase the airflow through the room during the day and turn it off during the night so it doesn't get so cold

I feel like i got some good advice!
Thanks for all the replies guys!

cottageman · Apr 13, 2021

Cookoo4Coco said:
My temps overnight this time of year can drop to the low 50s, My RH is generally around 40-45%

It first appeared when i was watering some seeds with a mister next to them at night. Obvious no no as the mist was hitting them and was making them damp a couple hours B4 lights off

I think Step 1 is continually treat the plants. My guess is that my H202 spray is killing the "tops" but not the "roots" of the Mildew
So im going to do a baking soda test tomorrow morning
Step 2 will be clearing all the plants next to my intake vents vacuuming and wiping down the walls wherever i can reasonably reach
Step 3 will just be waiting a few weeks and seeing if its clear before i put em into the flower tent. Just gonna be a low and slow veg in the clone area i guess.

Also i think i will increase the airflow through the room during the day and turn it off during the night so it doesn't get so cold

I feel like i got some good advice!
Thanks for all the replies guys!

I do a foliar spray once a week now of power si, cal mg, and either purecrop1 or ogbiowar foliar up until week 2-3 of flower. Plants have never been healthier and have been pm free for about a year and a half now

PWM on clones, Will i ever be able to eradicate it?

PWM on clones, Will i ever be able to eradicate it?

Cookoo4Coco

Oldguy71

KingTubby

Cookoo4Coco

KingTubby

Kanzeon

Anthem

Kanzeon

KingTubby

KingTubby

KingTubby

Powdery Mildew and Fungicides: Part 1: Background

Kanzeon

Is Powdery Mildew Systemic?

cottageman

cottageman

KingTubby

Is Powdery Mildew Systemic?

cottageman

The Connection Between Mildew and Calcium Nutrition in Agriculture

Wh1teScorp1on

Kanzeon

Cookoo4Coco

cottageman

Privacy & Transparency

Privacy & Transparency