easier said than done... I was only seeing in on the lowest leaves and it would spread up higher. It def is under control now and I'm barely seeing any... The lower leaves on it don't obvs see as much light.
PM on newly rooted clones
- Thread starter Meast21
- Start date
I grow in tents so its hard for me to get to the back of the tent bc I have neck issues so I just left some of the leaves on. The PM is def 98% gone after spraying with the Citric Acid like a week in a row... The pm always starts on the lowest leaves and works its way up... Should I still keep straying the citric acid everyday or cut back or what??
Any idea why it starts on the bottom leaves? ..Also is it more important to spray the bottom of the leaf or top of the leaf?
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I rather just keep spraying the bottom leaves all through the grow than to remove the leaves. Like I said my neck is screwed up and its hard for me to get to the back of the tents.
DCcan
Well-Known Member
Okay then, good luck with that. Removal of affected leaves is usually "Step 1" on any treatment.
(a) Initial infections are visible as white colonies on the upper surface of leaves.
(b) Scanning electron microscopic image through a cross section of a diseased leaf showing powdery mildew mycelium growing over the surface of epidermal cells. The underlying cells of the epidermis and mesophyll layer, and the lower epidermis, can be seen in this section.
(c) Abundant spore production from an older powdery mildew colony on the leaf surface
Evaluation of disease management approaches for powdery mildew on Cannabis sativa L. (marijuana) plants
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Just spraying isn't gonna work is that what you're saying? I 100% have to remove the affected leaves.Okay then, good luck with that. Removal of affected leaves is usually "Step 1" on any treatment.
(a) Initial infections are visible as white colonies on the upper surface of leaves.
(b) Scanning electron microscopic image through a cross section of a diseased leaf showing powdery mildew mycelium growing over the surface of epidermal cells. The underlying cells of the epidermis and mesophyll layer, and the lower epidermis, can be seen in this section.
(c) Abundant spore production from an older powdery mildew colony on the leaf surface
Evaluation of disease management approaches for powdery mildew on Cannabis sativa L. (marijuana) plants
Ok thanks... Why does it start on the lower leaves?
Drop That Sound
Well-Known Member
That's a good question. My guess is that it's not really the lowest, but more like the innermost leaves are affected most. Probably because the reast of the outer leaves block the air flow, giving the PM spores a better spot to land and germinate. I'm honestly not sure though. Maybe for the same reason other plant problems affect the lowest area of the plant first..
Drop That Sound
Well-Known Member
I caught PM like a week after responding to this thread, on my mother plant that's been slow vegging all winter without good fresh airflow. I sprayed a sample bottles worth of green cleaner I had laying around, a few times a week for like 2 weeks. Left a nice sheen everytime I did. It did keep wanting to come back still on the lower inner leaves, but I would rub it in good to the worst spots, and removed plenty of leaves. Haven't seen any since, for over a month now. I barely tweaked the environment much either, so ya green cleaner works good for PM too. I probably wouldn't buy it though, or spray around flowering plants..
Drop That Sound
Well-Known Member
One thing i noticed, is that being a big bushy reveg plant, the PM pretty much only attacked the mutated sections. It's almost like the plant didn't care if the PM took out only those leaves, and it left the new normal revegged areas alone. It went right for the massive twisted up 3 prongers that looked all jurassic first, even though they were incredibly healthy.. Just an observation, maybe all a coincidence. Maybe I need more insulation under the cold floorboards for winter, and now thats its warmed up and the floor isn't cold af is the reason it went away. You guys are onto something with that.. lol
DCcan
Well-Known Member
There's 2 systemic products that can be used to boost plant immune response, keep it healthy. Part of IPM, before the plant gets infected.
Regalia (pgr) and Reliant (fungucide). Both can be applied with foliar or chemigation.
Reliant contains 45.8% mono- and di-potassium salts of phosphorus acid. When applied, Reliant is rapidly absorbed across cell walls. It quickly translocates throughout the entire plant and kills pathogens on contact. Reliant also works as a protectant, making the plant resistant to further disease infection by thickening plant cellular walls to prevent mycelia penetration. Increases the plant’s production of phytoalexin antibodies that stimulate the plant’s immune system against disease.
Regalia (pgr) and Reliant (fungucide). Both can be applied with foliar or chemigation.
Reliant contains 45.8% mono- and di-potassium salts of phosphorus acid. When applied, Reliant is rapidly absorbed across cell walls. It quickly translocates throughout the entire plant and kills pathogens on contact. Reliant also works as a protectant, making the plant resistant to further disease infection by thickening plant cellular walls to prevent mycelia penetration. Increases the plant’s production of phytoalexin antibodies that stimulate the plant’s immune system against disease.
Is there differnt kinds of PM or is it all the same?
Yeah my PM started in the winter when temps reached 64 degrees with lights off.
Drop That Sound
Well-Known Member
Ya, there are many different strains of PM, but only a few specific ones that attack cannabis. Always floating around waiting for the right kind of leaf and conditions. I used to think it was all the same, and the diseased looking trees outside could spread it easily to my garden, but I guess I was wrong, and there are many different kinds... No idea if one cannabis/hops specific PM strain is more resistant than the other, but I can only imagine one could be?
Does citric acid stop spider mites or other bugs?
nxsov180db
Well-Known Member
More important to spray the top of the leaves since that's where the PM is, yeah PM usually does start on the bottoms, the RH swings are probably higher at the bottoms vs the tops, plus less light. You could probably just spray the bottoms daily or every other day if you wanted.