Powdery Mildew?

So my plant has been looking bad for a while, about a month ago I made a huge idiotic mistake of mixing some water that had sugar in it with a mister bottle I use to spray my clones and plants sometimes, well right afterward this crap started to show up. Started off looking like a light snow but now its effected almost all of my leaves and I am worried. I did some research and came up with Powdery Mildew, and perhaps something else. I read in the plant care guide that there is black spots and there are block dots on the leaves. The bottom of my plant is effected badly and most of the leaves are turning yellow and dying off. Except it’s almost like it starts off light and on the edges and works its way in. Like I said there could be something else.

So I was wondering if you could help diagnose, and what the easiest way to kill PM is?


And pictures would probably help.

Before we start; I suggest you fill out this support ticket. It will help us give you a more informed evaluation and remedy. :smile:

Answer these simple questions the best you can.
If you do not know, or do not use something; Just say so = NA

Strain; Type, Bag seed, or NA

Soil in pots, Hydroponic, or Coco?

System type?

PH of runoff or solution in reservoir?

What is strength of nutrient mix? EC, or TDS

Indoor or Outdoor

Light system, size?

Temps; Day, Night

Humidity; Day, Night

Ventilation system; Yes, No, Size

AC, Humidifier, De-humidifier,

Co2; Yes, No

Add anything else you feel would help us give you a most informed answer. Feel free to elaborate, but short, to the point questions and facts will help us help you :slight_smile:

I hope this helps you out it helped me big time

Powdery Mildew

Mildew spores can be brought into the grow room through air ventilation into your grow room, your cloths, pets and be carried by animals outdoors. and land on the plant infecting other parts of the plant, buds, stems, stalks and leaves, also spores can land on indoor grow room walls, tubes, growing equipment, hoods, ballast’s, cords and etc. Spores can remain dormant until environment factors trigger it, like high humidity and cool temperatures, poor air circulation. Powdery mildew in vegetative growth is much easier to rid than in the later stages of flowering. Night time temperatures and moisture triggers spores to be released. The mildew eventually covers and coats the plant thus reducing the process of photosynthesis. If left untreated powdery mildew will infect all plants in your garden and coat your plants in flour like substance and cause leaves to “suffocate” Yellow and die off. If your plants are in flowering, depending how far into flowering, your buds will eventually become infected and will not be able to be used. Buds will have a stale moist smell and will be coated with a white powdery substance that can’t be removed no matter what you do. Very early detection in flowering plants that have powdery mildew is extremely important, the longer you wait in flowering the more impossible it gets to eradicate this, due to this, bud size gets bigger in flowering and having high humidity temperatures over 65% can trigger active spores to start, not only powdery mildew, but triggers other problems from it, like bud rot. Not only will you have lower yield, but you won’t have any buds, due to the fact mold has crippled your harvest.
Strains vary in susceptibility to molds, just like other pathogens and nutrient requirements and care.

Prevent and Control

Symptoms of your plants having powdery mildew include: white blotches of furry stuff and white spots or splotches that you can wipe off, having humidity that is over 65%, also starts on darker areas of the plant and spreads to the top. Darker areas on your plant that do not get a lot of light will start to show this first, then when spores become active it spreads to everything. The longer you let it go the harder it will be to eradicate, late flowering plants that have this are extremely hard to get rid of, due to bud density thicker in late flowering plants, because of this the mildew attacks the buds which you can’t cure mildew once it affects the buds.(also known as Bud Rot)Plants that are stressed from environment factors, or fighting pest’s will be taken over more by this mold, due to the fact it’s already fighting problems. If you see your stressed plants getting it first, try to isolate the plant and bring down humidity, better air ventilation and or negative air pressure grow room. If you have mildew with your fans running, you will need to take them down and clean them as the fans can spread spores around the room. You will need to wash down everything in your indoor grow room, spores land on everything, so everything needs to be washed with mild hot water and bleach solution. Removing infected leaves from the grow room is critical, carefully removing them and trying to not knock spores into the air is a challenge. Applying a bag over infected leaves and tying it shut then removing it helps out with not knocking up spores in the air. Making sure you use h202 on stems that have open wounds from leaves that was removed. DO NOT water when


Damping-Off is a fungus that is in soil mixtures, it attacks seeds and seedlings before and after it emerges from the shell. Seedlings that get attacked by this fungus usually die, considering the plant doesn’t have a fighting chance nor a system setup to help fight the fungus. A range of growth stages the plant can be attacked, up to 8 sets of true leaves, or 3 leaf nodes. Leaves, roots, and stems can be affected. Damping-off can be easily confused by excessive fertilization (Nutrient Burn), high levels of salts from either water or nutrient solution build up, excessive heat or cold, excessive or insufficient soil moisture. The Cotyledons show on the soil surface can whither and die or healthy looking seedlings may suddenly fall over. Infection first starts right below the soil line; once attacked, the seedling and vegetative stage plants will start to rot, lower part of the stem will be soft, brown and or leaves will turn purplish hue and can yellow, brown and then fall over or shrivel up; can be any one of these or show all symptoms. Seedlings, or vegetative stage plants then can start to fall over from stem being so soft and starting to rot inside out, one item contributes to this problem is over watering, putting seedlings, or small plants into a big pot; when you water the soil down lower soaks up excess water and ends up sitting in the middle to bottom part of the soil in the pot. When this happens fungus begins to build up due to them not having a deep enough or a big root system to absorb all the excess water, then it ends up turning into damping-off. Later stages of damping-off in vegetative stage seedling, the leaves will droop and turn yellow, as if the plant was over watered. Stems will be severely weaken and may fall over from being under developed and skinny. Older plants can build up a resistance to damping-off, but if they do not, older plants show long skinny stems, stunted roots, and stem discoloration. The Soil that is rich in nitrogen, r rich mixture, and soggy soils, soil that stay wet for long periods, and warm soil or temperatures. Even hydroponics systems can get damping-off; mediums that stay too saturated, you have less likely chance of getting damping-off in hydroponics systems.

Prevent and Control

In order to help control damping off or preventing it you should try to start seedlings in “starter cups”, drinking cups you get from the store; putting drainage holes in the bottom of the cups is extremely important in helping avoid damping-off, allowing excessive water drain so the bottom half of the mixture will not stay wet.
This is why cups are great for starter seedlings, you can still over water, but your chances of getting damping off are much less than that of a seedling put into a big pot with lots of soil. Making sure you have holes and a good amount of perlite in your mixture helps greatly, I always recommend cups having drainage holes. Putting seeds into the soil at a low depth helps out, just putting it an inch or 2 at the most helps avoid the fungus.
Avoid starting planting in rich soil mixtures, not only can you burn them when they emerge out of the soil, but too much nitrogen can lack root growth and aggravate damping-off. Try using a seed starter mixture, not watering heavily, and avoid watering everyday, seedlings in cups should only be watered a bit every 2 days, seedlings with 2 to 3 sets of leaves in cups can start to be watered more heavily where water starts to drip out the drainage holes, only then you should water like this every 3 days. Over watering is one of the biggest causes of
damping-off. Also using soiless-mixtures like peat growing mixed with other stuff can help deterrent it. If you decide to get mostly soil with peat moss, you must make sure there is dolomite lime added to adjust the p H, otherwise you will have ph issues that can lead to locking out nutrients that are in the soil, but not able to be absorbed because the ph is off. Using sterile soil helps greatly, Allow great air flow and circulation in your grow room, allow the surface to dry before watering again, using moisture meters, or sticking your finger down in the soil near the edge of the pot to test for wetness down in the soil. Testing the soil near the edge of the pot helps to avoid bothering root development.
Once Seedlings that have already emerged from there seed shell and end up getting affected by damping off has a very high chance they will not survive and there is nothing you can do about it, by the time it shows in seedlings, it will already be to far gone. Using a fungicide on the seed before putting it into soil mixtures helps to avoid post emerge damping-off. Vegetative stage plants with a few sets of leaves has a better chance of fighting it off, using a fungicide can help depending on how far along the fungus has spread. Using any of these products below can help avoid or kill damping-off. (If using on seedlings or seeds, use organic based fungicides.) Chemical control should only be used on older plants, not seedlings.

Physan 20
Garden Disease Control
Multi Purpose Fungicide
Top Spin

Safer’s Garden Fungicide
Concern Copper Soap Fungicide
Guardian Angel
Serenade Garden Disease Control OMRI
Safer 3-in1 Garden Spray OMRI

Hope’s this helps it sure helped me out when had this problem


Thank you guys for the response. Here’s my ticket;

Strain; Type, Bag seed, or NA Bag seed

Soil in pots, Hydroponic, or Coco? Soil

System type? ???

PH of runoff or solution in reservoir? N/A

What is strength of nutrient mix? EC, or TDS No nutes except for what is in my miracle grow soil


Light system, size? Two CFLs, 1 LED 140watt

Temps; Room temperature, I believe in the mid 60’s.

Humidity; Day, Night N/A I know it’s not very high though.

Ventilation system; No

AC, Humidifier, De-humidifier, No

Co2; No

Does that look like powdery mildew to you guys? So what happened was I was trying some new things and I accidently mixed some water that I had poured a bit of molasses in with my regular water that I spray on my plant every few days, I am not sure if the sugar had anything to do with it but it seemed like that amped up whatever is happening. I’m worried though because it’s on all of my plants as of now and seems to be spreading. I would like to get rid of it before it kills them. I can post some more pictures as well if need be. On my first plant a few months back I was using to incandescent and they were producing quite a bit of heat and it was keeping my grow room really dry and warm but since I bought a cheap LED the heat has gone down and the humidity likely up.

Now i’em thinking maybe with that sugar could have attracted turips they suck the juice out of the leaf and it to will look a lot like white power mildew.
try and get a closer look and see if you spot any black spots here and there you may even see some mostly under the leaf


I do not see powdery mildew. Powdery Mildew is as described.

Your lack of the OH in your pot is an issue.

Not knowing, but assuming humidity is OK, is also a contributor to your issues. I have to assess this problem to you not providing the proper atmosphere for successful growing. We would love to help you correct these issues, but you have to adjust your grow methods; If you went to succeed :slight_smile:

I’ll be honest when I read this I didn’t think that was the case, but this morning before I went to work I took a look and sure as shit there were some black dots. I got a magnifying glass and they’re moving!!! Yikes, thanks a ton though. So how do I get rid of these little invaders before it’s too late? I am going to read up in the plant care guide after this.

Thanks, I don’t think it’s PM anymore either. Whatever it is (which I believe now is pests but I think theres a chance something else could be wrong as well) it’s new. From like Sept. through Feb. of last year/this year I did a grow in the exact same environment. I did have some slight issues but I was able to do a full grow of one plant start to finish. The only thing that has changed is my light and room temp since then. My other plant did not have these problems though.

I thought so… I just went through the very same thing. I don’t know where you live but if you live in the states go to Home Depot
and get your self some Diatomaceous Earth and power everything it looked liked it snowed in my grow tent but it cleared the tripes out in only days u must get under the leaves to don’t forget.

Thrips are really tiny, but can be seen by the naked eye. Some may have wings and some may not. Thrips reproduce rapidly, especially in tight places. That is what makes them hard to get rid of when using pesticides. The suck the sap right out of your plant with there piercing mouths, which makes the leaves look like they turned white. You can tell when you have thrips by taking a look at your leaves, the leaves will look as if there chlorophyll have been ripped right off the plant. Plants that are damaged can’t be healed thus making it harder for the plant to absorb light. SO if left untreated the thrips will kill the plants. Damage also can be seen by the greenish black specks of there poop they leave on leaves. Also the plants will show silver patchs from scar tissue. Depending on the severity at first, thrip damage might look like spider mite damage untill it increases in damage and then thrips case is for sure when you see the greenness replace with big parts of white.Thrips also can causes viruses to the plants and any larvae infected will breed more infected pests!. While they suck, the plants release honeydew which can contribute to mold on your plants. Adults have wings but do not fly well, but rather jump more. There are different kinds of Thrips, some more resistant to chemicals. Thrips can also carry plant pathogens in there mouths and carry it to other plants increasing the chance for your plants to get infected. . If your plants are affected during late flowering or close to harvest, please try to use the safest means of control to be safe to your health.


One good way to repel thrips for those growing outside is to use garlic, this is a good way to keep them away before you get them. The color yellow attracts the thrips and should be advised not to have this color around your grow… If you already have them using neem oil, and or lady bugs can get rid of them. If the infestation is bad then you need to use biological solution like, pyrethrin-like insecticides.

Other Products include:

Hot Pepper Wax,Safer Yard & Garden Insecticide (which can be used right to the day of harvest), GNATROL ( used in hydro in the water as well as soil),Doc’s Neem Pest Soap,Safer Sticky Stakes,TR-11000 Pyrethrum.

Hope this helps let me know how it go’s


Thank you, I went out and got some DE from home depot like you said, can you use this stuff in small spaces or is there anything I should be warned about? The bag says “safer brand” and says you can use it indoors. Should I coat every leaf with a bit or just some of the leaves? I am going to do some trimming and salvage what I can as my lower leaves are looking real bad now. I pray this plant pulls through. About 3 weeks ago it seemed like it was growing like a weed and now it’s not grown in like the last week and I hope this solves it.

I looked it up and this stuff seems to be pretty safe. I made it snow on my plant. Should I also sprinkle some on top of the soil? I gave my plants a bit of water with some 50% ISO alcohol in it to try and kill off anything living in the soil, that’s the hope at least.

Heres a video I took before the DE application. What are these little buggers? I don’t know if they look like the thripds or whatever they’re called. Another thing I have noticed is small spider web type deal which leads me to believe I may have spider mights as well. I also saw some brown bugs while looking along with those black ones. I recently got a job at a nursery where I work with plants every day so I am wondering if maybe I brought home some of these bugs on my clothes or something. I’m freaking out though I don’t want my plant to die.

One last thing, how do you guys apply the DE? I just dipped my fingers in it and then sort of painted it on my plants.

get it all over the plant and soil and you should be ok in a couple of days
let me know


I think it should take care of the spider mites if you see webs…and ya when you get home from work it would be a good idea to change your close


Yea, unfortunately though my grow room and my closet are the same space, and I don’t have a bedroom so it also is my changing room most of the time. I just went in there and I could see those little buggers hanging from webs on the leafs. I want them dead!! I’m praying this will fix my problems, I wish I caught it sooner but I want to thank you garrigan for helping (You too LW) if you hadn’t said anything I probably would have not caught them. I don’t really expect there to be bugs in my closet.

Hopefully it’s not too late. My plant is really not looking good…well right now it looks like an albino MJ plant.

You are very welcome, Like i said mine was cleared up in a few days. So hang in there by Wensday you should be get to go.


Thank you, I will update on how it goes. Praying my plant can recover. I plan on getting some ILGM seeds soon though so I guess if there was a good time to restart it would be now. I can see tons of bugs crawling all over now…They must not like it. They look like tiny spiders dangling from their webs. Is there anything I should do in the future to prevent these guys again? I have like 2 or maybe three types of bugs though. How likely is another attack after using the DE? Should I regularly use it to prevent these guys?

Unfortunately in the last few days my clones started to shrivel up for reasons I have no idea of… The walls are coming down.

DE will work for quite awhile, unless you rinse it all away. Light reapplications to the top of the soil and around the stem will also prevent new infestation of critters, like spider-mites and such that need to lay their eggs in the soil.

Thank you, I was going to ask about that as well, how long should I leave it on? I put it on pretty thick in some places and I was wondering if it is going to affect the leaves blocking light or something. From what I understand this stuff physically effects them and they die over a time, so that means they can’t really get use to it right? Yesterday afternoon they started really moving, hours after I had coated it but then I got a spray bottle and added it on thick and the spider mites bailed from the leaves and are mostly hanging from webs. They went crazy with some web spinning though, I think they’re trying to make a house or something to get out of the DE. Looks like it snowed all over. I also put in/on my soil and is it OK just to water as usual?

It affects their exo-skeleton, scratches it causing them to dehydrate more easily and it get’s in their joints as well, it can also dry them like a desiccant, also all the scratches make them more vulnerable to getting infections that can help kill them off. They can’t really build up an immunity to it.

You will want to wash it off well, a good pure water foliar spray a few times should work, at least by around the last weeks of flowering, it won’t hurt you if it is on the buds when you smoke it, but it won’t taste good.

You can water as usual, you might want to reapply a little to the soil surface, but most of it will water in and mix with the soil, but won’t necessarily go anywhere, and it will keep doing its work in the soil to anything digging around in it.