If you are just entering the world of growing cannabis, there are unfortunately many issues that you’ll have to deal with. Of course, at the end of it all, there is a big reward for you, plenty of potent and flavorful buds. With that being said, there are many obstacles that you might have to deal with along the way, and mold and mildew is one of them.
The unfortunate reality is that mold and mildew pose fairly large threats to your cannabis plants, and even worse, they can happen fairly easily. Both mold and mildew can start growing without you even knowing it, and all of the sudden, you have a huge infestation with all of your plants being totally covered.
Not only do mold and mildew look really bad on weed plants, but they can be extremely detrimental as well. In more ways than one do mold and mildew negatively affect the growth of cannabis plants, and in the long run, may even kill them.
Today, we are here to figure out what exactly mold and mildew is, why they’re bad for cannabis plants, why they grow in the first place, and how to get rid of them. Our main goal for today is to help you avoid having mold and mildew grow on your cannabis plants in the first place, with our secondary goal being to help you get rid of it if it does grow.
What is Mold and Mildew?
For those who don’t know, both mold and mildew are types of fungi that can grow in many different environments, including both in indoor and outdoor spaces. First, we have regular mold, which is a type of multicellular fungus that can take the form of many different colors.
It usually has a cotton-like or fuzzy texture, and grows in large colonies. It usually grows in very humid and damp conditions, and can grow on many different organic materials, including plant matter and soil, such as your weed plants.
It spreads by releasing tiny spores into the air which then land on other surfaces and start the process of new mold growth. This can be a very common problem when it comes to cannabis growth.
We then have mildew, which is actually a specific type of mold that grows primarily on damp surfaces like wet soil and on plant matter.
Here, you’ll usually notice some kind of white, grey, or yellow powdery growth. It’s much more likely to affect living plants than it is inanimate objects, which include leaves, plant materials, buds, and fruits. Mildew is usually less harmful to human health than mold is, but it’s still not good for plant matter.
What Do Mold and Mildew Look Like on Weed Plants?
If you notice that there is some kind of fuzzy, powdery, or cotton like growth occurring on the soil of your cannabis plants, on the leaves, or on the flowers, then it is likely that you have mold or mildew.
In most cases, this will look very fuzzy and feature a white or yellowish color. It might look like there’s a thin layer of white or yellowish powder growing on your plants and on the soil below. If you see fluffy white growth, you’ve got mod and mildew.
Why Are Mold and Mildew Bad for a Cannabis Plant?
So, if it’s not necessarily poisonous, you might be wondering why mold and mildew are detrimental to growing cannabis plants.
The reality is that they are both actually very bad for cannabis plants, and this is true for a number of reasons. Let’s take a look at what these might be.
Trouble with Photosynthesis
Perhaps the biggest problem that cannabis plants encounter when the leaves are covered with mold and mildew is that they get much less light.
Photosynthesis is the process where fuel is converted into food for the cannabis plant, and this is a process that requires sunlight. If mold reduces sunlight exposure for the cannabis plant, it will also reduce photosynthesis, therefore stunting its growth.
Poor Respiration
Another problem that can occur when mold and mildew infest your cannabis plants is that they clog the stomata, which are the very small openings on the leaves of the plants. These are very important for the respiration of your cannabis plant.
If these openings get blocked, then your weed plants can no longer exchange gases like oxygen and carbon dioxide with the environment, which will lead to decreased respiration, and ultimately to poor plant health and stunted growth.
Fewer Nutrients
Yet another issue that will occur if your weed plants get infested with mold and mildew is that they can both be parasitic to a plant, which can cause nutrients to divert away from your weed plants.
Of course, nutrients are extremely important for cannabis plants, and any kind of nutrient deficiency can have a drastic impact on the overall health of the plant.
Weaker Immunity
Something else to consider here is that cannabis plants that have mold and mildew on them may also have a much weaker immune system, due to the detrimental effects of the mold.
The combination of reduced photosynthesis, poor respiration, and being able to absorb fewer nutrients may result in a weakened immune system, which may then make it easier for disease to take hold. Weakened immunity is a very real problem here.
Loss of Your Product
Overall, not only can all of these factors lead to the death of your cannabis plants, but having buds that are infested with mold or mildew is no good either way.
The simple reality is that if your cannabis buds are infested with mold and mildew, they won’t taste or smell right, and they can even pose certain health risks if you consume or smoke them. In other words, if your cannabis buds have mold on them, they are effectively garbage and are no longer viable for use.
This goes so far as the legal realm, because in legal cannabis cultivation, if cannabis is infested with mold or mildew, it will most likely fail quality control tests and no longer be allowed for sale. Not only will buds smell musty, but it can totally ruin cannabis flowers and all plant material in general.
Why Do Mold Spores and Mildew Grow on Cannabis Plants?
Something that many people wonder is why mold and mildew spores start growing on cannabis plants and in the growing medium. Many people wonder where the spores came from. Now, the reality is that both mold and mildew spores are in the air all around us.
However, the difference is the environment, as well as other factors, which determine whether or not that mold and mildew can actually take hold and start to multiply. There are a few different factors that can lead to mold growth, so let’s take a look at what these might be.
Humidity
One of the biggest factors that will contribute to mold growth is high humidity. Cannabis plants that are grown in indoor conditions are often held in fairly humid environments, which is great for mold growth. If your grow room is very humid, it provides mold with a perfect medium for growth. Humid conditions are always conducive to mold growth.
Poor Airflow
The next factor that will most undoubtedly lead to mold and mildew growth in your cannabis grow room is if there is poor ventilation and a lack of air flow. If there is poor inflation and a lack of air flow, it will make high humidity conditions even worse, and also create conditions where a lot of moisture can accumulate. This also means that mold spores have an environment in which they can multiply in.
Temperature Shifts
First and foremost, realize that hot air holds on to a lot more moisture than cold air, so it’s more common for mold and mildew to grow in very hot grow rooms. Furthermore, if there are a lot of temperature fluctuations, it can also lead to condensation growing on the cannabis plants, with condensation acting as a great medium for mold growth. The growing environment makes a huge difference.
Dense Canopies
Something else worth considering is that if the canopies on your weed plants are very dense and thick, it will reduce light penetration and air flow.
This will create what are known as microclimates within the cannabis plant canopies, which will it be more susceptible to the growth of mildew and mold.
Something you also need to be aware of is that there are some cannabis strains that are just more susceptible to growing mold and mildew than others.
Ways to Get Rid of Mold and Powdery Mildew on Weed Plants
If your cannabis plants have become infected with mold and mildew, there are some ways you can get rid of it.
Now, one of the big tricks here is to catch the mold and mildew before it really begins to spread, which means that you may have to get rid of one or two plants that are infected before the mold and mildew spreads to all of the plants.
Quarantine the Affected Plants
To prevent mold on weed from spreading further, and to treat powdery mildew, the first thing that you want to do is to isolate moldy cannabis plants.
Cannabis mold can spread very quickly from one plant to another, so if you see mold on cannabis plants, you immediately need to quarantine the affected plants and put them in their own location.
You do not want to keep them in the same location with healthy plants, as this will aid in preventing mold from growing on other cannabis plant leaves in your whole grow room.
Increase Airflow
Another good way to help get rid of mold is to increase air circulation. If you increase air circulation, it will help to kill mold because it will automatically lower the humidity level, therefore making the conditions less favorable for mold to grow.
Furthermore, with increased ventilation, especially if you have a good outtake system, you can cause a lot of the mold spores to be sucked out of the grow room and to go outside.
Decrease Humidity
Something else that you absolutely need to take into account here is that you need to decrease the relative humidity, as this will prevent mold from spreading to the surrounding plants, and will also prevent it from growing in general.
You want to decrease the humidity to as low as you can go without affecting the weed plants negatively due to the air being too dry. If you lower the relative humidity in the grow space, it should go a long way and controlling mold on all the plants.
Defoliate and Prune
To help increase air circulation around the canopy of your plant, it’s a good idea to do some defoliation and pruning. If you make the cannabis canopy a little bit less dense, it will provide mold with less opportunities to grow.
Maintain Temperature
Mold likes relatively high temperatures and high humidity levels, therefore a good way to help control it is to maintain a steady temperature that does not allow condensation to form, as well as a relatively low temperature that cannot hold on to a lot of moisture.
Taking proper precautions like this in the first place can go a long way in preventing this white powder and other types of mold from occurring.
Increase Lighting
Mold generally likes to grow in darker conditions, so an easy way to kill someone and to prevent more of it from growing is to increase the lighting intensity in your growing space.
Use Fungicides
Of course, if you already have a very serious mold and mildew infection, creating an airy environment, decreasing the temperature, controlling the humidity level, and more, although all beneficial, will likely not be enough anymore.
Therefore, you’ll want to use some kind of fungicide, whether or natural unlike neem oil or a professional and chemical based fungicide, to treat mold and mildew. What it really comes down to is that if mold and mildew have already taken hold on your marijuana plants, using a dedicated fungicide will be one of the best and only ways to get rid of it.
