Your pm is coming from low sap ph most likely caused by a calcium deficiency or potassium deficiency. Or low sap ph caused by over application of nitrogen or phosphorous depending on how you look at it. At the end of the day if the plants are even half way on point with 6.0+ sap ph, and even decent brix levels you will not get pm even with 24 hour power outages and the warm humid dark perfect pm growing conditions the power outage would cause.
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the first one I noticed it on was in a cloner. Now that plants mom spread it further. What to do to prevent low sap ph? How to test it? bust a stem and rub on a ph strip? I run organicish with pbp liquid nutes and coco. also its only as far as a few spots but Im treating it. Im guessing ill get through this harvest fine but saw it on younguns today. How long is residuall on eagle 20? If you put eagle on a mom and take clones then they will be clean or dirty?
Grab a good quality metal garlic press and pull how ever many leaves with large petioles necessary to get a large enough sample for your ph measurement device of choice. Roll the leaves and petioles in to a ball and “juice” it with the garlic press. It’s a lot easier with a horiba laqua meter that only needs a couple of drops. Since you have an active infection I can already tell you with absolute certainty that your sap ph is low. Anions lower sap ph, cations raise sap ph.
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how to prevent or cure low sap ph?
Don’t use eagle 20 because you’ll be forever reliant on it due to using it as a crutch. I have no clue how long it stays for, I’m a compliant cat 3 operator. To increase sap ph increase your cations. With an active infection, I would also foliar cations using insecticidal soap as a wetting agent… get 2 birds stoned at once.
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Nobody should be using eagle 20. Its banned in California for a reason and your making extracts with that…
I recommend both of these products.
https://www.doctorzymes.com/mo/natural-non-toxic-insecticide.html
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ive grown a long time but you are using unfamiliar terms. How to increase cations?
Im using milk, potassium bicarb and soap.
\it may be coming off my lawn. Im doing lawnwork and see a youtube channel in my area and he has pm on the grass.
Your cations are magnesium, calcium, and potassium. Google sap ph and brix and how they relate to powdery mildew. That’s as far as I’m willing to spoon feed. And spraying any of that crap on your plants only treats the symptom of an underlying problem.
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the other thread says cal mag as a cure all is a joke. I got over 100 grows in a row under my belt so saying not spoon fed is goofy. I didnt understand what you were getting at with sap I see no references in any literature to pm. do cucumber farmers try and keep sap ph up?
No one said a damn thing about cal mag. That is high in nitrates.
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you said mag and cal, I guess its not cal mag plus.
I dont usually ever get pm in spring but my old go to when I had it before was zone and penetrator. or a sulfur burner I havent used in years
You choose how to fix it and what products you want to use. But your cation to anion ratio is wrong and any commericially available cal mag I’ve seen will just make it worse.
This has been very positive for quite a few that I know of.
Increase you air flow in low lighted areas
i dont use it often and prolly not on this grow at all. but I do have cal mag plus = and every other shit from the store. greencure is cancelled, i using milk and potassium I already described my issue- it was going from 86 to 66 due to freezing cold leaking in the ac unit. thats a pm farm I switched teh lights to on at night, that should help. Its strange to see the whole tents dark in the day= means I got time to clean shit.
My main greenhouse is in desert hot springs California and has no heat. My recent temperature swings are pretty much exactly the same and I don’t have pm. There is a reason for that. Google cation to anion ratio and sap ph.
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I just googled a lawn guy and he has pm on his lawn near me- I think its prevalent here this year. ive only got it in fall in the past.
An idiot operates a greenhouse next door to me with pm (and every other pest) and I don’t have it. I could also easily kill it on any lawn or prevent it in any crop using nutrition. So could you, if you would Google what I told you to Google and quit trying to figure out where yours came from. All plants tell you exactly what they need, you just need to learn how to listen to them…
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