Bud Rot: What Is it, And How To Avoid It

What Is Bud Rot?

With the increase in marijuana’s popularity, there is an emerging problem that has been making the grower’s life miserable, and that is mold. Cannabis is very vulnerable when it comes to mold.

A Must-Read: Sativa Keeping You Awake at Night?

If your cannabis is not stored properly, mold can ruin your entire stash. Moldy bud is typically easy to spot, as it looks like a wispy white fuzz.

If you think it may not be as dangerous as it looks, think again.

What is bud rot? Bud rot is a common fungus that many cannabis growers face. It is especially common among farmers who are unfamiliar with humidity control and air circulation. This fungus is so severe that it prevents the plant from getting water and nutrients.

In this article, learn all about bud rot and what exactly it is. To avoid rot, you must know its signs and its possible causes. Check them out below.

The Definition of Bud Rot

Bud rot is most commonly known as gray mold. It is a fungal disease that lives best in cool, humid, and temperate climates.

Contrary to popular belief, it is not a location-specific fungus. In fact, it attacks marijuana plants in all stages of development.

Gray molds come from a fungus called Botrytis cinerea, which can easily rot your buds from the inside out.

This is why gray mold’s nickname is bud rot. Botrytis can also ruin other plants besides marijuana.

Bud rot can easily track and reach out to all your plants at any time of the day.

This is because it can spread through its dusty gray spores, which can easily be transported through wind and water.

The plant itself must come into contact with gray mold. Aside from that, a gray mold infestation can affect your other plants, like wine grapes, strawberries, and peonies.

Once the gray mold reaches its target, it will get inside the plant by entering through a wound or a tear in the plant’s tissue.

If you are training your plants, the stems will have cracks that mold can easily go through.

Another factor is that if there is any damage caused by snails, caterpillars, worms, or other pests, this can create a tunnel for the gray mold to get in.

The Physical Characteristic of Bud Rot

When it comes to appearance and characteristics, it can be quite hard to detect bud rot in the early stages.

The reason is that the fungus is actually targeting the plant on the inside and not the outside.

During its early stages, bud rot can affect the stems of the bud.

The worst thing about this is that it is impossible to see from the outside, though the stems will start to turn a little gray and have a gooey consistency.

As the rot starts to infect your buds further, you will see that some of the leaves will turn yellow.

Aside from that, you can observe that they will start to wilt. The buds will start to develop a gray web around or on top of them. This is a pretty good sign of bud rot.

Meanwhile, if you see some dust and webbing, it is pretty late in the game to save your buds.

The reason is that the whole plant is probably infected as well. These white spores are what infect all the healthy parts of your plant, and they can be transferred from one plant to another, either by water, wind, or your clothes.

If you suspect that your plants are infected with gray mold, the best way to figure this out is by looking between spaces in the buds.

If the bud’s inside is brown and mushy, you should immediately isolate the plant from the others.

Worst-case scenario, if most of the bud is compromised, you need to throw out the whole plant and look for signs of infection in your other plants.

The Signs of Bud Rot

Bud rot first attacks the stem of your plants. See if they appear mushy and gray in that area.

As the infection increases, you will see some signs like wilted, yellow, and burnt leaves.

This is the most tricky part because it is nearly impossible to spot this ahead of time, as the fungus attacks the inside of the plant and works its way outside.

To catch bud rot, look between cracks and crevices of the suspected buds to see if the core is rotting.

If the core seems soggy and brown, immediately bag the plant, remove it from the other plants, and quarantine it in an enclosed area.

After that, investigate other plants’ physical characteristics to see if the bud rot has spread.

If you see another plant with bud rot, follow the same procedure.

Probably the most common sign of bud rot is the development of gray webbing or dusty white spores.

These spores are problematic because they can be transferred by wind, water, and other pollinators.

You can also be the culprit, as spores can stick to your clothes and get to other plants that way.

To prevent the transfer of spores from one plant to another, make sure to change into a different set of clothes between rooms or just wear a protective suit for each room.

The Causes of Bud Rot

Bud rot normally occurs if your environment has poor air circulation and high moisture conditions.

This encourages the fungi to grow and flourish.

However, rot does not happen overnight, and it is pretty common in larger buds and some dense plants because they can easily trap and accumulate moisture.

Additionally, multiple plants that are close together are a high risk for infection.

The good thing about the indoor growing method is that it is less likely to result in this kind of issue.

This is because, in an indoor setup, you can control the environment when it comes to temperature, lighting, ventilation, and humidity levels.

This is more of an issue with outdoor growers because they can’t control the weather outside, and it has the potential to be saturated on a daily or nightly basis.

Outdoor growers need to have a leaf blower. This is a great tool for removing excess water from the plants.

You can do this every morning to blow the dew off your plants or after heavy rain.

This is a very effective way of drying them off so that they do not sit wet for a long period of time.

An electric blower is the preferred one to use because gas blowers contain fumes, which can be harmful to your garden.

Bud Rot Treatment

When it comes to treating bud rot, there’s nothing you can do to reverse all the fungus’ damage and spread.

If you find a section of your garden that has gray mold, there is a high probability that the rest of the garden is infected, too.

You can only prevent the fungus from spreading any further and remove all your infected plants.

This way, you can save some of your plants, though some farmers, at this point, will harvest the plant immediately.

If you are trying to save what you can, when you spot a sign of bud rot, the first thing to do is to remove the infected buds carefully and try not to expose them to your other plants.

You can wear gloves to remove and discard the infected bud and place them in sealed storage, so the spores don’t spread throughout your growing room.

If your plants are in the flowering stage, avoid using fungicides, neem oil, or sulfur because these kinds of treatments will affect the buds’ taste, smell, and appearance.

Bud Rot Prevention

As cliche as it sounds, it is better to prevent things from happening than to cure an ailment.

Environmental control is the answer to avoiding bud rot. Here are some recommendation to follow in preventing bud rot:

Air Circulation

Clean air is important, and it should move continuously throughout your grow room.

This will prevent the spread of all harmful pores or diseases present in your surroundings. A good example of this is using a floor fan.

Humidity Control

Humidity is also key to preventing the spread of harmful spores. A good dehumidifier can remove excess moisture in the air and reduce the likelihood of mold and mildew.

Spacing Between Your Plants

Space is the most important factor in preventing the spread of the fungus. Your plants should not touch each other, and air should flow freely between them.

Inspection of Your Plants

Daily inspection can help you see the growth and state of your plants. Remove any standing water and unnecessary plant material in your growing room.

It is very important to inspect your pets thoroughly on a day-to-day basis to catch the disease in its early stage or, better yet, to prevent bud rot from happening.

Bud rot can be hit or a miss, but if the plants are all in the same environment or room, it is most likely that the fungus will spread.

The fungus needs a moist environment to survive and germinate. Once it shows up, it will survive if you have not taken action to create a better environment.

Preventing Bud Rot When Growing

To prevent bud rot, especially during your plant’s growth stages, you need a good set of growing conditions and the right maintenance.

As you know, bud rot can thrive in growing rooms that have a high humidity level, poor ventilation, and slightly warmer temperature.

Your plant can easily get bud rot if it is bushy, has very dense buds, or has poor genetics.

You can avoid getting bud rot if you select the best genetics for your grow space. Always look for highly-resilient plants.

If you cannot offer higher-end growing conditions, you should opt for growing Sativa-dominant plants.

Preventing Bud Rot When Drying

Even if you do everything you can to prevent bud rot, it could still appear after harvesting. Bud rot can happen during drying and curing.

This is why it is necessary to check the temperature and, most importantly, the humidity levels of your growing room or drying room.

To deal with this, you should have an appropriate location in your drying room. Also, you need a relative humidity of 60%, and the temperature has to be around 15 to 25 degrees Celsius.

If you have issues with the humidity level, you can always opt for wet trimming instead of dry trimming.

By this, you remove the excess plant material that contains water, which will allow for better airflow and lower humidity in your drying room.


In conclusion, bud rot is an annoying and nasty problem when it comes to plant production.

It not only can spread in all your plants in the growing room but also make your buds turn gray. As a result, your buds will be unsmokable.

What’s worse, it will basically destroy all the time and investment you put into plant production.

When you spot bud rut, follow all the tips and prevention methods mentioned above.

It is always recommended to provide the best environment for your plants to grow properly and healthily to avoid problems.

Recent Posts