Hey, I am cleaning my room very well and using regalia as a drench and foliar. I’m still getting little outbreaks. Air flow is perfect. Wondering if my mini split could have pm in the system? I’m cleaning every part of the mini split I can get to. Running dehumidifiers and follow VPD chart. I’m at a loss. I killed everything in my stable of genetics to make sure I’m not keeping it around on cuts. I’m growing everything from seed now to make sure nothing already sick with pm is still around. I disinfected the tools , scissors hoses and even cleaned every bottle of nutes. I’m at a loss. Anyone have any ideas and what about the mini splits? Anyone have any luck with UV light?
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A/c units are great for housing all kinds of shit you don’t want. I was told to use a air conditioning coil spray expanding foam for a.c coil cleaning. You also have to be careful if you use your condensate water.
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Let us also not forget, mildew spores travel in the air. Regular cleanings only make sense, right?
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whats your RH and temps? maybe just stray from your VPD chart a bit and keep the humidity lower. is it on several strains or just one? I believe PM is also systemic so if your mother plants have it you may keep seeing breakouts, might have to start fresh. but to answer your question you could, is there some type of filter you could use? would ozone generator kill PM in the air?
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Ever tried a foliar application of sulfur in veg?
VPD chart is only accurate when all other growth variables are optimal.
Environment is perfect at all times. Running 2 quest 110 overheads and 6 24,000 btu mini splits
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I was basically trying to find out if the mini splits can get pm in the system. I’m building a 200 light facility and will be using these old splits in the veg and dry and cure rooms and wanted to make sure pm in the lines is not a possibility . Thanks
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Worrying about what’s on your mothers, or in your A/C is the wrong approach imo.
There are mildew spores in every breath you take. Mildew can only develop when provided proper conditions.
From wiki:
Mildew requires certain factors to develop. Without any one of these, it cannot reproduce and grow. The requirements are a food source (any organic material), sufficient ambient moisture (a relative humidity of between 62 and 93 percent), and reasonable warmth (77 °F (25 °C) to 88 °F (31 °C) is optimal, but some grown can occur anywhere between freezing and 95 °F (35 °C)). Slightly acidic conditions are also preferred.[5] At warmer temperatures, air is able to hold a greater volume of water; as air temperatures drop, so does the ability of air to hold moisture, which then tends to condense on cool surfaces. This can work to bring moisture onto surfaces where mildew is then likely to grow (such as an exterior wall). Preventing the growth of mildew requires a balance between moisture and temperature either in such a way that minimal moisture is available in the air and the air temperature is low enough to inhibit growth (at or below 70 °F (21 °C) without causing condensation to occur, or by in such a way that warmer air temperatures, without an actual change in the amount of water vapor in that air, is by its nature “drier” (has a lower relative humidity) than cooler air and will tend to inhibit mildew growth in this way. Warm temperatures coupled with high relative humidity set the stage for mildew growth.
That’s the thing my environment is perfect not sometimes but always.
Pardon my ignorance but what is PM?
I assume the M stands for Mildew.
One thing to remember is there are things which do not require such levels of moisture. Dry rot anyone?
I am currently fighting something like that, I had a small leak behind a partition wall which then spread moisture through a wider area which then became a source of infection for some sort of mould/mildew thing. Looked a lot like calcium deficiency but under the microscope you could see it was some sort of black mould.
I have increased my airflow, sorted all leaks, and I am being harsh with pruning and removing any leaves with any sign of anything.
Touch wood, it seems to be fine now. I will know next time I take cuttings, the humidity shows which plants have been affected.
IMHO if you are building a 200 light system and re-using any old parts you are doing it wrong. You want no possibility at all of anything transferring from an old system to one that size.
Personally, anything over a four light system gets brand new kit throughout. Then the only infections you get are new ones.
what do you keep your RH and temps at? trying to maintain perfect VPD could be your problem. like at 77*F it’ll tell you to be at 75% RH for perfect VPD which imo is ridiculous. should never be over 55% in flower and then it’ll tell you to be at 59F-66F which is also ridiculous
@MicroDoser PM is powdery mildew
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Ah, thank you
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I don’t know how to make this any more simple. Mildew only develops when provided adequate moisture. The problem is the environment, not dirty equipment.
You can scrape all the mildew out of that A/C and blow it through my grow room circulation fans. It won’t grow on the plants or surfaces…because it can’t.
Being in the green range on a vpd chart does not mean your environment is perfect in any way. It just means if all other growth factors are optimized, the plant will maximize potential metabolism.
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Greeting guys, one thing worth mentioning is that powdery mildew (PM) and mildew (M), while both being a fungus, are two different things. There are other factors relative to “powdery mildew” outbreaks then environmental conditions. Powdery mildew is systemic and needs a host plant to reproduce.
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You’re right. I will sandwich up my words.
I’ve only ever seen it in rooms with large day/night temp swings.
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That’s a fair observation though. Mold spores are omni present. Even though powdery mildew needs a host, it still prefers certain conditions to proliferate. The threshold of the day to night shift is critical…
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