Getting rid of powdery mildew

Help for sick or damaged marijuana plants. Marijuana growing pests, diseases, nutrient problems.

Well I got some starts from a friend and they developed powdery midew at about week 3 of flower on my C99 girls. The strain is known to be susceptable, so I don't know if it had it before I got it, or developed on my watch. I limped along with Greencure(sodium bicarbinate) and harvested 5 days early, but had to toss some of it. My night temps are a controlled 72F, but my humidity runs 45-55%, depending if I water or not. I'm planning on upping my exhaust from a 4" to a 6 or 8", but what do I need to kill any spores that are remaining in my room? I've heard that if you can raise the temp to 140F it will kill the spores-anyone concur? Guess one might want to have a fire extinguisher handy. Will bleach kill it? I don't want to be be messin with that shit again!

get rid of it with 3-in-1 spray.. cheap and easy to find....

no home remedies-- and no bleach anywhere it might come into contact with the plants-- it WILL kill them!
KARMA:
No need for revenge, just sit back and wait.
Those who have hurt you will screw eventually themselves; and if you are lucky, God will let you watch!


Through What we create- we are immortal.

Thanks for the reply LZ, The bleach that I was refering to is the Ona brand. I believe it has a chloralease agent in it so that it doesn't affect the plants. I used it for cleaning hydro gear before switching to dirt. It has a part A and part B and you only use 2 oz of each with 25 gal h2o. The guy at the hydro store said it will kill PM. Regardless, I have the room empty for a few days and wanted to do a thorough eviction of all PM spores. Are you sugggesting spraying the room down with 3 in 1? I picked some up today to use on my vegging girls before putting them in the flower room. How long does it last, as far as keeping the PM away, or is it just another temporary band aid? If I don't put any more plants in the room will the PM die, or will the spores always there? I hate this shit almost as much as the borg! I smoked a bowl of dryed, but not cured from this batch and the first hit I could taste the shit, then it was gone, even after tossing anything that looked even minutely effected when harvested, but I'm not into smoking mold. Guess I'll have to Iso the batch. Again, I want to make sure this doesn't happen again! Has anyone heard about the 140F heat for dealing with PM? Thanks, BnS

If the room is totally empty-- use a very fine mist sprayer and some Peroxide (3% solution in brown bottle) mixed at 1 part to 2 parts water and mist everything in the room... wear eye protection and a dust mask!

let it dry....

treat EVERY plant prior to going into the room with 3-in-1.....

make sure there is a high airflow in the room...
you can not get milder/mold if there is a real good air-flow and no new contaminants!

we have 2 "cyclone" fans, an 8" 750 cfm fan (running a carbon filter & blowing back into the room) and an oscillating fan in our 10x11 room... the plants are in constant motion- have very strong branches, and never have a mold/mildew issue- even when the humidity goes up!

Good luck-- once you get these issues, it is a constant worry for a while-- but once it is gone and stays gone a while-- you'll have more "peace of mind"... just keep up the air circulation, and mist the plants with 3-in-1 at least 1x every 3-4 weeks (1 hour before the lights come on... or turn em off an hour if vegging) until the issue is gone!
KARMA:
No need for revenge, just sit back and wait.
Those who have hurt you will screw eventually themselves; and if you are lucky, God will let you watch!


Through What we create- we are immortal.

Thanks for the reply LZ. The rooms been empty for a week, but I've been too depressed to do any work in there-had to toss nearly a pound of 2 different varieties! Monday I'll take your advice and peroxide the room. I already have the 3 in 1 and will apply to the waiting girls while there still in the veg room. My bud room is only 5'x7' and I presently have a 4" 170 CFM exhaust fan and 1 cyclone, with an 8" passive intake. I'm planning on upping to a 6" exhaust and I'll add another Cyclone and I'm thinking that should be sufficient, but if anyone has advice I'd welcome it before I buy another fan. I got by with the previous 4" for several crops before this PM issue presented itself, but my next crop is running out of space in my veg room so I have do something soon! Thanks, BnS

Something cut and paste Bud

Powdery mildew develops quickly under favorable conditions because the length of time between infection and the appearance of symptoms is usually only 3-7 days and a large number of conidia can be produced in a short time. Favorable conditions include dense plant growth and low light intensity. High relative humidity (RH) is favorable for infection and conidial survival, but infection can take place at RH levels as low as 50%. Dry conditions are favorable for colonization, sporulation, and dispersal. Rain and free moisture on the plant surface are unfavorable, however, disease development occurs in both the presence or absence of dew. Infection can occur at 50-90°F; mean temperatures of 68-80°F are favorable. Powdery mildew development is arrested at daytime temperatures of 100°F or higher. Plants in the field are often not affected until after fruit initiation. The leaves are most susceptible 16-23 days after unfolding.

Contary to popular belief, powdery mildew generally does not require free water to establish and grow. Infection can actually occur on dry leaves. Warm temperatures and shady conditions encourage the fungus to grow and spread. However, the spores and mycelium are sensitive to extreme heat and direct sunlight.

The optimum temperature for infection is between 68 to 77 degrees F and relative humidity between 40 to 100% is sufficient for the spores to germinate. Low, diffuse light also seems to favor powdery mildew development. The mildew can spread rapidly since the disease cycle can be completed in as little as 72 hours. However, it commonly takes 7-10 days from the time of infection to the development of symptoms and secondary spore production.

Quote:
Plant in full sunlight in a well-drained area.
Do not crowd plants. Air flow and ventilation will discourage mildew growth.
Powdery mildew thrives where high rates of nitrogen have been used. High nitrogen promotes tender leaf formation, causing dense stands that are more susceptible to infections. Adequately fertilize but avoid stimulating succulent growth. Organic fertilizers or slow-release formulations of lawn fertilizers are good choices.
Prune infected plants to get rid of infected parts and increase airflow. If the infestations are severe, remove and destroy the plants that are infected.
Disinfect your pruning tool in a bleach solution of one part household bleach to four parts water after each cut.
Watering plants in the morning gives the plants the rest of the day to dry off, discouraging establishment of diseases, including powdery mildew.

Hope it helps a bit

Peace
If my penis is 12" long. Is it a Foot?


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