What are you using for PM in flowering?

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zem

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The place where I have to be and grow my plants, is impossible to dial humidity and temperature fluctuations enough to prevent PM. The only effective way to completely eliminate it up until now for me is by removing the strains that are prone to get it but this is very restrictive and I am growing very nice strains that do get it so I am always trying to find ways to battle it during flowering, and I need to do this with what is available for me locally (not in the US) and I don't have amazon or such services. All what is available here are chemicals that I don't want to use on flowers and I tried many remedies so far. The most effective ones for flowering plants are monopotassium phosphate(MPK) and milk. I think MPK is a bit better plus I worry about spraying fats that are in milk on my buds in fear of partially dissolving them and damaging them, although i did not notice ill effect when i did, I lean more on MPK. Sodium bicarbonate is effective for vegging but it damages the pistils by making them dark in color so I don't use it in flowering. I tried to spray silica on vegging plants and it was not effective with one application, maybe it needs several more and/or by injecting it into the feeding by roots so it gets in systemically, i will have to try it again. The one that surprised me by being not effective was lactic acid. It simply did very little effect to combat PM, and milk on its own is way more effective. I recently found a product called Pyrroloquinoline quinone I sprayed one vegging plant yesterday to try it. What do you peeps use on flowering plants to battle PM? I might find a way to get it if it will solve my problem entirely.
Thank you for any advice.
 
A tablespoon of hydrogen peroxide (3%) in a gallon of water does pretty well against PM, and you can spray that on buds with no damage. I've read some spray it at 3% right out of the bottle, but I never tried that.

I don't know if I would spray PQQ on buds. A lot of PQQ products warn against inhaling it.
 
Peroxide has worked for me. Silica needs to in the medium and fights pm systematically. Also lost coast plant therapy. The most effective way I've eliminated pm has been to limit foliage by removing fan leaves over time. Too much foliage traps moisture and limits airflow. The only time I don't defoliate is during stretch at the beginning of flower. Also spray the peroxide or whatever you're using on the base and bottom branches of the plant. Not just the leaves. Pm seems to start there on my plants.
 
Unless you're in flower... micronized sulphur will eradicate PM on contact. Also handle mites with ease. I use it monthly in veg. EzPz.

Had serious PM issues in the past. Once upon a grow it was so bad I had to shut down amd start from scratch.

Good luck.

Edit... sorry @zem I have baby brain. Had to reread the title of you post. My bad.

Will say though, using this in veg will keep it from occurring in flower...

Again, sorry!
 
I guess I've been blessed. I've never had PM in an indoor grow. I keep four fans going in a vortex constantly and maintain a clean room that would put an operating room to shame. Never had spider mites or thrips, either.
Outdoors? Yep. Got a Michigan monsoon a couple of weeks before harvest time, but it was more bud rot than PM.
 
I have used h2o2 on plants before and within a couple of hours the leaves were oxidized and turned golden and then brown. I was trying to battle mites at the time i think i used 1ml/liter of 35% h2o2 that is 0.035%. I decided since that time to not use it on leaves ever again.
 
A tablespoon of hydrogen peroxide (3%) in a gallon of water does pretty well against PM, and you can spray that on buds with no damage. I've read some spray it at 3% right out of the bottle, but I never tried that.

I don't know if I would spray PQQ on buds. A lot of PQQ products warn against inhaling it.
I want to know more about pqq. I tried it on a vegging plant it did no damage i am waiting to see positive results. Do you know if pqq can be used on budding plants through feeding the roots instead of spraying the buds?
Peroxide has worked for me. Silica needs to in the medium and fights pm systematically. Also lost coast plant therapy. The most effective way I've eliminated pm has been to limit foliage by removing fan leaves over time. Too much foliage traps moisture and limits airflow. The only time I don't defoliate is during stretch at the beginning of flower. Also spray the peroxide or whatever you're using on the base and bottom branches of the plant. Not just the leaves. Pm seems to start there on my plants.
What do you mean by " lost coast plant therapy"?
I'm with the guys above. I've used it on outdoor grows and the h2o2 works good. Pm is a sign of a environmental tweak is in order. What's your VPD run in there?
I have a greenhouse which cannot be controlled with electric power dehumidifiers heaters or coolers. I only use fans so i have to battle pm in another way. Temperature and humidity fluctuations will result in pm on strains that are prone to get it unless i intervene in some way. I am trying to find systemic treatments like silica but incorpprating it in a fully functional system with the limited time that i have has been slow so i was not able to use it in my res and feed the roots with it consistently and i plan to do that soon. The VPD is one thing that i still dont know howvto measure. I have rh and temp readings.
 
I want to know more about pqq. I tried it on a vegging plant it did no damage i am waiting to see positive results. Do you know if pqq can be used on budding plants through feeding the roots instead of spraying the buds?
I didn't find anything on PQQ being used specifically with cannabis at all. I don't think it's approved for commercial cannabis use, but I don't think it's banned either. It's used with vegetable growth, though, to boost growth and inhibit "pathogens" including an array of fungi.
 
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I understand the greenhouse struggle. I did a greenhouse grow a few years back in Alabama. Daily temps over 100 and constant humidity. Every day I'd be greeted with a new bug or mold. Shade cloth and fans was all I had to move air and try to subdue the suns heat. I used a lot of silica when I watered. It was supposed to help with the heat stress. Maybe it did..i dunno. I remember standing inside of it when complete thinking how in the **** am I going to grow in this heat..lol. I made it happen and ended up with maybe 3-4 oz of bud rot the whole grow. Not bad for a dozen big plants and a crap ton of clones sea of green.

Cannabis is a pretty tough cookie.
 

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Hard to grow when it's hot and your plants aren't in open air where they can breathe good.
No way I could grow in a greenhouse in Texas in the summer heat.
Now the winter would be a good time to grow in a greenhouse.
Glad you still got a harvest.👍
 
if the greenhouse has straight roll up sides like mine and with proper shading, it becomes cooler on the inside than on the outside. It is not the heat that i am battling but PM that results from fluctuations in temps and humidity. Right now monopotassium phosphate and milk are working okay, but i still have to apply every 4-5 days. I am trying to find something more reliable. I started with the silica in the veg area and waiting to see results. If i wanted i could cull out a couple of indicas and i will solve it permanently because these are the only ones where it is getting a grip on. But one is my favorite OG kush and i want to have the ability to grow new strains with less of this obstacle.
 

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