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Moldy weed

How to Stop Moldy Weed

Moldy weed can occur as a result of a number of different reasons, no matter the reason, mold on weed is never good. In this article, we will look at the different types of mold and how to solve them

Did you know that bugs and pests aren’t the only living beings snacking on your cannabis plants? That’s right. Marijuana mold is a common problem for weed growers the world over, and the fungus can’t get enough of your delicious green ganja.

Sure, it’s normal to see a bit of green fuzz on the sandwich you forgot about at the back of the fridge, but how can you spot mold on weed? Can it do severe damage? What might happen if you smoked it?

You’ve likely got a lot of questions in your head now about cannabis mold, but don’t worry. We’re here to help.

Read on to find out all the answers and get to the bottom of your weed mold issue to get rid of it for good. The time to attack the fungus head-on is now!

What is mold on weed?

If you’re picturing the white and green powdery substance on an old apple that smells bad, then you’ve got the right idea. Moldy weed looks similar in many instances. Despite its unattractive appearance and nasty odor, it’s essential to your cannabis plants.

As we mentioned before, mold on marijuana likes to munch on your weed crop, but the fungus doesn’t have a digestive system. Instead, it emits enzymes that break down substances, like plant matter.

Mold on Weed

Mold is one of Mother Nature’s great decomposers as it helps eliminate waste, dead plants, and deceased animals before returning them to the earth as tiny particles.

If this conjures up images of the opening sequence in the Lion King, it should. Fungus is a massive part of the circle of life, although cannabis growers suffering from moldy weed might hesitate to agree.

Once the white stuff begins to spread, it can cause significant distress to your marijuana plants and destroy whole cannabis crops if not dealt with effectively. Knowing how to spot and treat mold on weed is crucial. Keep reading to learn what to look for.

The different types of mold on marijuana plants

To combat the issue, you need to know what you’re dealing with. A lot of weed growers confuse trichomes and moldy cannabis because they look similar. Treating your marijuana plants when they aren’t sick can do more harm than good, though.

Let’s take a closer look at three common types of weed mold and how to tell them apart from trichomes and other issues.

White mold on weed

Cannabis powdery mildew is a collective term, as many varieties exist, but they all affect your marijuana plant in the same way; you’ll see a fine dust-like layer on the leaves.

White mold on weed can look like trichomes, so you’ll need to get out your trusty magnifying glass to tell the difference. The latter gives your cannabis that ever-so-familiar aroma and looks like shiny crystals, whereas fungus is powdery.

At the beginning of a white moldy weed infestation, you’ll spot a few tiny patches that move onto larger areas on the lower leaf level. As time progresses, so does the fungus as it infects branches, stems, and flowers.

How to spot white mold on weed:

  • Patches of white powder on fan leaves
  • Plant tissue changes color
  • Growth slows down, and leaves look distorted
  • Signs of infection of new leaves and flowers

Black mold on weed

If you’re not dealing with white fungus, your cannabis plants might fall victim to black mold on weed. This type appears as a dark powder on leaves that looks like soot and flakes easily. Sooty mold is easy to spot, making it easier to treat quickly.

You’ll see small black patches form that spread and cover the entire surface of your weed plant’s foliage. As the fungal infection expands, it disrupts the cannabis crop’s photosynthesis, which can stunt growth.

How to spot black mold on weed:

  • Other bugs around your cannabis plant, like aphids and whiteflies
  • Black patches on leaves that look like soot
  • Stunted growth

Bud rot

One type of mold on marijuana plants that many growers will tell you they’ve had an issue with is botrytis, better known as bud rot. This cannabis fungus makes its way into your precious weed plants via openings and wounds.

It doesn’t matter if you’re growing indoors or outdoors and whether your cannabis crop is healthy or not; bud rot tends to find a way to attack. It’s tough to avoid because it’s almost always existent in the atmosphere.

Botrytis is well-known for doing irreversible damage. Once this marijuana mold enters your greenery, the spores spread quickly and can infect the whole plant and the rest of the family, too.

How to spot bud rot:

  • Small dotted patches of black or grey mold
  • Extensive, fuzzy gray areas
  • Shriveled buds and leaves that go brown and then die
  • Tips of leaves change color to yellow then brown
  • Infection that spreads fast

What causes mold on weed?

Mold on pot plants or your garden crop can appear at any stage of your weed’s life. Even if you make it close to the end, the last two weeks before harvest are when weed mold is most likely to strike.

It can be deadly and ruin all the fruits of your labor and the chance of a delightful fat joint at the end of it all. That’s the opposite of what you want.

The first step to combatting the problem is to identify the causes and do something about them. The two most common are a humid environment and a dirty grow area. Let’s take a closer look at how they create the perfect climate for cannabis mold to take over.

High humidity

Your beloved marijuana thrives in hot and humid conditions, which is, unfortunately, what mold loves best. Your weed plants transpire the water they absorb into the atmosphere, attracting fungus gnats on cannabis and mold.

Cannabis humidity

It can be challenging to balance the need to grow healthy weed and keep mold on cannabis at bay. You need to be vigilant and avoid over-watering.

Dirty grow space

There’ll be times when you’ll tend to your plants or perform tasks that cause a lot of mess and dirt. This is another factor that encourages moldy weed to form.

Cannabis grow room
Keep your grow room tidy like this one!

Set up a ‘dirty room’ that in no way connects to your grow space. Make sure they don’t share the same air conditioning, heating, or ventilation. Incredibly, marijuana mold can transfer up to eight feet from one space to another without any help from the air.

Mold reproduction through spores

Sadly for you, moldy weed can appear with very little encouragement. The fungus reproduces spores that are almost everywhere in the atmosphere.

The best thing you can do to control mold growth is to prevent it from happening with the right cultivating environment.

How to prevent mold from occurring

Creating the perfect growing setup is essential from day one to avoid a moldy weed problem. You’ll need to take a slightly different approach if you grow indoors compared to what you would do outdoors.

To stop mold from intruding inside, you’ll need to:

  • Set up fans to prevent stagnant air.
  • Avoid overcrowding of plants and regularly prune and trim where necessary.
  • Use a humidity monitor to check the levels.
  • Perform a quality check often on your weed to spot mold when it first appears.
  • Opt for cannabis seed strains that can withstand fungus well.

If you grow marijuana outdoors, use the following techniques to prevent moldy weed:

  • Regularly shake your cannabis plants to get rid of dew and rainfall.
  • Set up your grow space where your weed will get plenty of sunshine and breeze.
  • Plant in pots so you can move your crops during bad weather.
  • Don’t plant cannabis close together.

How to treat moldy weed

If prevention methods failed and you come face to face with a fungus issue, you’ll need to know how to get rid of mold on weed.

The best way to attack the problem is to harvest the infected cannabis plant as soon as possible. It might sound drastic, but the consequences could be devastating.

Once you spot mold on weed, more spores will be floating around in the environment. The longer you leave the issue unattended, the more time the fungus has to spread to the rest of your cannabis crop. Remove the sick plant immediately to avoid more destruction.

If you don’t notice weed mold until your buds fully form, you’ll need to chuck it. You might feel like lighting up anyway, but smoking fungus can do a lot of harm. You could experience anything from coughing and wheezing to nausea and vomiting.

The final toke

At this stage, you should know what to look for and how to spot moldy weed. If your cannabis plants become prey to the dreaded fungus, you know how to get rid of it and prevent it in the future.

Growing marijuana is an enjoyable pastime with wonderful rewards at the end. If you haven’t started your cannabis cultivating journey yet, it’s time to pick up some weed seeds and give it a go yourself.


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