What’s on my plant leaves ?

Could this be powdery mold? Only on 8–10 leaves from one of the my 3 plants that are in week 3 of flower.
It does rub off but not easily…..almost looks like dried bird crap….while I know there aren’t any birds around, could it be bug waste??
Could it be perspiration ? I was awfully sweaty one day while messing with them….
Whatta ya think???

Are you running a humidifier ? If yes are u using non r/o or distilled? if yes your humidifier is dispensing stuff like calcium into leaf’s.
it also could be if ur foliar spraying same thing or product itself

it also could be even perlite dust, like if u were up-potting moving medium/new soil and it got moved around via air


wipe/wash plant off and see if it come back. Take a macro/close up shot before and see if it’s “pm” puff

Thanks for the reply….I was able to rub a tiny spot off and it stayed on my finger, so I looked at it through the jewelers loupe. It looked like dried salt and broke up into that type of texture.
I use distilled water in my humidifier now but didn’t start until the grow before this one. And over time there was a white chalky powder that started accumulating on everything.
I wiped everything down good but I still find remnants of it.
I cut my humidity down to around 50-54% after I flipped to 12/12 and I think I have pretty good air flow through the space. I have a 4” exhaust fan running 24/7 and 2 fans blowing under the canopy and just above it…..so I can’t imagine it being mildew/ mold.

I think your ll good.I wouldn’t suggest besides end of flower to follow lower rh = sop for mold
plants exp if higher temps need that higher rh, key is having healthy plants and enough airflow and co2 based on ppfd/light intensity . For example in veg and if using led’s your gonnea be using a way higher rh ( above 70% while lights on )

what I mean is follow your temps and base your rh on vpd requirements. since like in nature the temps of the plants will be in cooler temps and best results also with treated such ( vs high ppfd and temps) to lower your light strengeth ,co2,nutes and temps at that time (2-3 weeks before harvest) and gradually do so. when having temps lower you will noitce like all vpd graph higher the temp on canopy equals high rh .

to have a good sop/prevention of mold like pm and budrot I suggest having as much airflow as you can. Biggest mistake I see is many people will only have wall mounted/canopy level fans. meaning it’s really Important to have airflow in the canopy and even on the medium if not hydro setup. airflow And healthy plant is your biggest sop/prevention for mold vs “low rh”.

if you don’t know what vpd is, here’s a great guide. There wireless environment monitor is an amazing tool for knowing the true temps,rh,pressure,vpd,co2 and u can be alerted also if anything is off. that tool payed for itself and than some in first round And really showed me why I had some issues in my rooms.


pulse environmental monitor

compassionateExotic said:

I think your ll good.I wouldn’t suggest besides end of flower to follow lower rh = sop for mold
plants exp if higher temps need that higher rh, key is having healthy plants and enough airflow and co2 based on ppfd/light intensity . For example in veg and if using led’s your gonnea be using a way higher rh ( above 70% while lights on )

what I mean is follow your temps and base your rh on vpd requirements. since like in nature the temps of the plants will be in cooler temps and best results also with treated such ( vs high ppfd and temps) to lower your light strengeth ,co2,nutes and temps at that time (2-3 weeks before harvest) and gradually do so. when having temps lower you will noitce like all vpd graph higher the temp on canopy equals high rh .

to have a good sop/prevention of mold like pm and budrot I suggest having as much airflow as you can. Biggest mistake I see is many people will only have wall mounted/canopy level fans. meaning it’s really Important to have airflow in the canopy and even on the medium if not hydro setup. airflow And healthy plant is your biggest sop/prevention for mold vs “low rh”.

if you don’t know what vpd is, here’s a great guide. There wireless environment monitor is an amazing tool for knowing the true temps,rh,pressure,vpd,co2 and u can be alerted also if anything is off. that tool payed for itself and than some in first round And really showed me why I had some issues in my rooms.

The Ultimate Vapor Pressure Deficit (VPD) Guide

"Why devote an entire guide to VPD?" you might ask. The answer is that the vapor pressure deficit (VPD) is extremely important for growing plants. VPD helps you identify the correct range of temperature and humidity to aim for in your grow space. With VPD you can achieve the best results while...

pulsegrow.com

pulse environmental monitor

Pulse Pro

The Pulse Pro offers enhanced grow room monitoring with CO2, PPFD/PAR, light spectrum, vapor pressure deficit, temperature, and humidity tracking. This advanced monitor boasts real-time and historical data, customizable alerts, and support for multiple sensors and WiFi networks. Crafted in the...

pulsegrow.com

Click to expand...

Thanks man….a lot of good info. I’ve tried to follow VPD and been able to keep things in line.
i ran my canopy temps at 79/80F thru Veg and the first week or so of Flower. Humidity is pain in the ass…..not so much controlling, but getting consistent and accurate readings.
I have 3 different hygrometers in the space, not including the rh probe on the inkbird. They are all fairly nice pieces and none of them read the same % at one time. I realize the rh is different down near the floor VS above the canopy but it feels like I’m shooting at a target in the fog.
Anyway, the only other issue I’ve had w/ VPD is my air temps compared to the leaf surface temp.
I bought a cheap infrared thermometer and it always tells me that my leaf surface temps are higher than they should be. Maybe it’s just the unit that needs calibrating, but there’s no option to do so.
My understanding is w/ LED lights, the leaf surface temp should always be a few degrees lower than the air temp. Well according to my thermometer it’s just the opposite. I’m veg I would have the temps at the canopy level at 79-80F and the infrared thermometer would read the LST at 82-83F.
This would mean my plants were having major transpiration issues, which has not been the case.
So for purposes of VPD, I always assume a LST of 2-3degrees lower than my air temps and dial the RH in accordingly.
Now that I’m 3 weeks into flower, I’ll try to keep my canopy temps at 76-78F and RH around 50-54%. For the last 3-4 weeks I’ll take the temps down another couple degrees and try for a RH of 45% or so. I get paranoid once it’s down the last week or so and will really drop the RH below 40%.
All that is assuming it’s not 95F outside with super high humidity levels, which it is right now.
This grow should be finishing up in early-mid Sept and I’m praying for some milder temps outside. The last few days it’s been 96-97f outdoors and I’ve had my AC unit blasting and still can’t get the canopy temps down below 80F.
I’ve been able to open the closet door to keep things in line but I can’t do that everyday.
I should be fine by September….I hope.

Jizz flakes?