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Marijuana Mold | What does Moldy Weed look like?

weed mold cannabis mildew

Nothing causes a grow operation to go sour faster than moldy cannabis. If you notice mold on marijuana plants, you have to take action fast. You need to resolve the issue and learn the best way for of preventing it from ever happening again. We’re here to help!

There are two main types of mold on marijuana that you’re most likely to notice on your plants:

  • White Powdery Mildew (also known as White Fuzzy Mold)
  • Botrytis (commonly known us bud rot)

In this article, you’ll learn how to identify these types of molds on your plants, what to do when you find them, and how to keep from having to deal with them again.

Looking for marijuana seeds?

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Grow your own magical marijuana plants at home with the best-selling Vivosun Hydroponic Grow Tent.

This super sturdy grow tent will keep all the wanted rays inside, and any unwanted rays out. Zip it up, but peer through the observation window whenever you want to check on your little plant buddies.

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Alright, so we're talking a different type of grass than what this little boy is inspecting, but the tool still functions the same!

Equip yourself for a successful grow campaign with the right tools. We recommend one of those tools be this 30X magnifying glass. With that much zoom and an LED light, you'll be able to examine plant tissue for unwanted growth.

cannabis mold sick plantThis is one of the more painful articles we've had to write! @Grow Weed Easy

Identifying mold on marijuana buds

Some molds, like the white fuzzy mold, are very easy to identify once visible, but others, like Botrytis, may be a little more difficult to identify until it’s too late. That’s why it’s so important for cannabis growers - aspiring and expert alike - to know the best growing practices. By inspecting your plants regularly, managing humidity levels and room temperature, and knowing what potential dangers look like, you can help your plant material develop properly, and you and your friends will never smoke moldy weed!


White Powdery Mildew

White powdery mildew appears just as you would expect it to with that name: it's like it’s growing a little patch of fuzzy white powder in a spot on the leaves of your plants. If you find this white mold on marijuana plants in your crop, there are a couple of methods you can try to rid yourself of it ranging in cost, amount of supplies needed, etc. You can find white mold marijuana pictures online with a simple search.
Here are some things you can try: 


Botrytis (Bud Rot)

Botrytis tends to be a difficult marijuana leaf mold to identify. It starts as a small brown mold that sets in at the base of the stem. Most growers don’t notice any moldy weed symptoms - the beginning stages of moldy weed are difficult to detect with the naked eye - until small leaves on their plant start to wither, discoulor, and, finally, dry out. If the bud is kept in high humidity with low air circulation, it’s basically being kept in a breeding ground for mold development. Mold growth will turn into a decomposing sludge in the final stage, while low humidity can cause it to crumble when it’s touched. This isn't some fictional horror story; it really happens, and it can have serious repercussions for human health. Nobody should be smoking moldy weed! Not only does it taste bad, but it can also cause lung infections and other health problems.

You can find this particular type of mold on marijuana pictures online through a simple search.
Here are some things you can do to rid yourself of botrytis: 

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You've put the work in to grow your plant babies into beautiful, potent marijuana plants. Now, to properly enjoy it, get yourself a  vaporizer that can do it justice!

With the Linx Gaia vape, you get a thoughtfully designed dry herb vaporizer that quickly and evenly heats your bud to your desired temp. Because of its temperature control settings, you could even use it to smoke medical marijuana, as you'll be able to activate the desired compounds in the weed.

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Master glass blowers at Empire Glassworks have really outdone themselves with this precious pipe covered in sea creatures.

Whether you're an amphibian yourself or you merely want to show your love for these colourful creatures, this Great Barrier Reef glass pipe will have you feeling closer to your reefer than ever before.

bud rot gray mold weed
Bud rot is tricky to catch because of its subtle on-set. @Emerald Report

When are your plants most vulnerable to mold?

While it’s possible for mold to grow on your marijuana at any stage in its life, there are a few occasions where it is more likely to crop up. It’s important to make note of these times so you can be sure to inspect your plant thoroughly during the time it's vulnerable.

The late flowering stage

In the last few weeks before harvesting time, your buds are extremely susceptible to both types of mold. The denser and larger the buds of your plants are, the easier it is for the mold to grow and thrive. As the mold matures and takes firm hold, you’ll notice a discouloration of your buds.
Look for obvious signs of mold, bud discoloration, and sudden appearance of yellow spots on weed leaves.
If botrytis is the mold plaguing your plants, it’s a better decision to just go ahead and rid yourself of all the infected plants. You may think it’s worth it to save what you can, but the only way to save any of your crops is to remove the risk for them to be contaminated. Cut your losses and save the rest by removing and trashing all the infected plant matter.

cannabis flower rot unhealthy plant Presence of mold can be hard to spot, so make sure you're tending carefully to your herb. @Royal Queen Seeds

When the plant is big and leafy

White powdery mildew is the type of marijuana white mold that thrives in areas with hot, humid conditions with minimal to no air flow. When your plants are at their biggest, leafiest stages they take up more space, restricting the airflow around the plants even more, creating an ideal environment for this white powdery type of mold to grow in.


During the drying/curing process

One fatal mistake a lot of new growers make is letting their guard down during the drying and curing process. They think the hardest part is over and don’t pay as close of attention at a time that their product is highly susceptible to mold. 

Drying and curing your bud the proper way helps to prevent mold from growing. Make sure you follow each step in this process closely without skipping any whatsoever. You also want to be sure to inspect your buds regularly so if anything does go wrong, you’ll know soon enough to take action.

moldy marijuana kush Don't let this happen to your flower! Keep a close eye on it while it grows. @High Times

What to consider when you find mold

If you find mold, you don’t want to quickly act without a plan. Here are a few precautionary steps you can take and things you should keep at the forefront of your mind as you plan how to handle moldy weed treatment. 


Regularly inspect your plants carefully

Inspecting your plants often is the first step to discovering the mold early enough to save your plant, let alone the rest of the crop. At times when your plant will be highly vulnerable, check it more frequently. If you see something that looks like mold, take the extra few minutes to address it early on.


Harvest the whole plant at the first sight of mold

If you’ve spotted mold, that means that 1) the environment your plants were in causes your plants to be susceptible and 2) mold spores have already been introduced to your crops. You’re better off trying your best to save whatever is left to save.


Control your temperature and humidity

The more hot and humid grow rooms are, the more susceptible to mold your marijuana plants become. Set up your grow space in a room where you have complete control over humidity and temperature, being sure to monitor them both very closely.


Consider if the plant is worth saving

You want to inspect the plant thoroughly once mold has been discovered. If the plant isn’t worth the effort of saving, you’re better off saving the rest of your crop by ridding the grow space of the infection as soon as possible.

If you’ve found something that looks like mold, it’s important to act fast, but think it through thoroughly first.

Act quickly, not rashly.

moldy marijuana cannabis herb
It can be hard to say goodbye to your buds, but it's best an infection doesn't spread! @Grow Weed Easy


Nothing can ruin your entire marijuana crop as quickly as mold in marijuana. Marijuana with mold is difficult to deal with but, unfortunately, it’s incredibly easy to end up accidentally growing moldy weed, despite how hard you try to prevent mold. No one wants to smoke moldy weed, so grow with care, and those little buds will grow up into the potent, tasty buds they were meant to be!
Unfortunately, bud washing isn’t possible, making moldy weed removal and moldy cannabis control very difficult. While you can research how to get rid of mold on marijuana plants until you’re out of options, it’s far better to just remove the infection and not take the risk of infecting the rest of your crop.

What you learned:
  • Can the cannabis plant grow mold
  • How to get rid of mold on marijuana
  • Prevent moldy weed
  • What causes moldy weed

Now that you know how to get rid of mold on weed, here are our final thoughts:

  • Never try smoking moldy weed
  • If you discover bud rot, stop it immediately
  • Remember mold marijuana plants must be disposed of
  • If you find mold marijuana in your crop, inspect the rest of your crop thoroughly


Can’t get enough? Do you need to read more weed articles? Check out these fascinating topics:


Megan Medeiros Written by Megan Medeiros (BA)

Megan Medeiros has a bachelor’s degree in English and is currently working on a master’s in English at James Madison University. She's the owner and operator of Medeiros Writing, and has been working as a cannabis writer for the past three years, mostly following the legal climate of marijuana, especially in areas like California, Colorado, Oregon, Canada, and other legal areas.

This post contains references to products from one or more of our advertisers. We may receive compensation when you click on links to those products. For an explanation of our Advertising Policy, visit this page. All photos were sourced from | updated 2021

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