I have horrible news.
If your plants have powdery mildew, you’re probably going to have to destroy them.
If only a few buds are affected, you may be able to save the rest, though.
There are a few possible remedies, including spraying the buds.
You can even spray shortly before harvest time. Obviously, this does depend on what you spray them with.
There are really only two good options. We’ll cover them below, along with some non-spray remedies you might be able to try.
- 1 Spraying Buds Before Harvest: Powdery Mildew Remedy?
- 2 Spraying Buds For Mildew Before Harvest: Final Thoughts
Spraying Buds Before Harvest: Powdery Mildew Remedy?
This should go without saying, but do not spray your buds with harmful chemicals, especially right before harvest.
There are only two things you could spray on them that might work. But success is far from guaranteed.
No matter how you cut it, you are in for a lot of extra work if you want to get rid of the mildew. And the chances of success are low.
If it has only affected a small number of buds, you might be able to remove those buds and salvage the rest of your morning harvest. But you have to be very careful not to spread the mildew further.
Either way, keep reading for some possible remedies. Before we get to that, we’ll cover some things you need to know about powdery mildew.
We’ll also cover precautions to take to avoid getting it in the first place. That section of the article is easily the most important. Nothing gets rid of mildew better than not getting it in the first place.
What is Powdery Mildew On Buds?
Powdery mildew is a fungal disease that looks like white or gray powder. It usually first shows up on the leaves vegetative growth stage. Then it makes its way to the buds, which is where things get sad.
The spores are airborne and spread fast, once they are in your grow tent or the area outside the tent. There is no guaranteed way to assure you will never get any of this garbage on your plants, but there are things you can do to make it unlikely to happen.
Is Powdery Mildew Dangerous?
Yes. It is not going to kill you if you smoke a little on a bud or two, but it can lead to serious infections of the lungs. If you are an immuno-compromised person, it can really mess you up if you smoke too much of it.
Like other molds, it is best to avoid getting it inside you, whether swallowing it, smoking it, or just breathing it in. If you see it on your plants, wear a face mask to avoid getting the spores in your lungs.
Most people that have smoked bud with powdery mildew on it report that it is just a little harsher and may cause mild irritation. But those are healthy people.
Like anything else, it can really hurt compromised people. And if you smoke enough of it, even a healthy person can get extremely sick.
The bottom line is: powdery mildew is more than just an inconvenience if you find it on your buds. It is serious and must be removed.
And some other types of mold are downright dangerous. How do you know if you have one of these types? Read What Does Mold On Weed Look Like? for help in learning to identify it.
Unfortunately, that is almost impossible, so you will probably have to trash the buds (I know its hard to imagine). You really want to avoid getting the stuff in the first place.
Avoiding Powdery Mildew In The First Place
This fungal disease flourishes in the same temperature environment as cannabis plants. This makes things a bit difficult, because you cannot keep it out just by having your garden at a certain temperature.
Technically, you could but it would not be good for your girls… more on that later. But there are measures you can take. The four best ways to avoid an infestation are:
- Limit access. Restrict who or what enters the grow tent, since this junk can travel on shoes, pant legs, and even your loyal dog Skippy. Negative air pressure in the grow tent helps, too.
- Control your relative humidity religiously. If you keep it around 50%, you should be able to avoid the white powdery death. Some growers like to keep the humidity higher, but this is a big risk, especially if you are growing a dense strain.
- Ventilation is key. Keep the air moving, especially the exhaust. If some spores get in from outside and are blown out through the natural process of ventilation and exhaust, you may save your harvest. Get the best fans for your grow tent you can afford.
- Get a fancy air sanitation system. There are some high end systems that claim to remove all pathogens or molds from the air. This can get complicated if you already have a full ventilation system and humidity system in place, but if you are growing commercially or have a large garden and a good budget, this is recommended.
What to Do if You Find Mildew On Your Buds Before Harvest
There are so many different opinions and passionate discussions about this, it is mind boggling. We will limit this discussion to only legitimate, useable information
This means we will leave out all of the more insane remedies and stick only to science based solutions. You are welcome.
Cut Off The Infected Buds
This only works if you find the infestation early enough and it has only affected handful of buds. Cut off the infected ones and put them in a sealed bag. Get the bag out of the room and change your clothes afterwards before you go back in.
If you caught it early enough this may be all you need to do. As you are cutting, you need to be incredibly careful, because moving the plants may cause the powder to spread.
Hydrogen Peroxide Spray
Mix some hydrogen peroxide and water in a spray bottle. Spray all the affected areas of the plant and let it dry. The solution will kill the mold, but it comes at a cost.
It will also cause oxidation, which will burn the buds and greatly reduce the terpenes. Fewer terpenes kills the aroma and can also reduce the effects of smoking the bud (different terpenes are responsible for different effects).
Remember when I said more on that later? Well, here it is!
Although the ideal temperature for growing cannabis is the same as this powdery mildew, the fungus cannot handle high temperatures.
You could place your buds in high heat for a time and the fungus will all die. However, this also dries out the buds and nearly ruins them in the process.
Yep, radio frequency treatment. This is probably not something every hobby grower has access to, but it is an amazingly effective way to kill the fungus without harming the plants.
It will cause some loss of moisture and terpenes, but it is a much more limited loss than the previous methods. That makes it worth the gain.
Milk And Water
Mix some milk (whole organic is best) with tap water and spray the affected plants. Then let it dry completely.
This method takes some time, but it has the benefit of not using anything toxic on your buds. The key with this method is to make sure you allow the plants to fully dry.
You may want to crank up the temperature for a while after the treatment to help evaporation. But do not increase humidity.
The last thing you want to do is introduce more humidity into the room. After all, that is how you got in this mess to begin with!
Spraying Buds For Mildew Before Harvest: Final Thoughts
In most cases, powdery mildew means the loss of a harvest. But if it has only affected a few buds, you may be able to save the majority of your harvest.
We’ve given you a few possible courses of action, including two sprays you can use. None of the options are perfect solutions, though. There is no guarantee they will work well.
That’s why the most important part of this article is the one with steps to take to minimize the chances of getting powdery mildew in the first place.