Smoking Moldy Weed - Symptoms, Smell, Detection, and Prevention

Smoking Moldy Weed – Symptoms, Smell, Detection, and Prevention


Smoking moldy weed is a bigger problem than most people think in 2022. It’s more common than laced weed and can occur at any time if there’s enough moisture.

Anyone who has smoked weed more than a couple of times has probably inhaled mold.

Some molds are harder to detect and prevent than others. But fear not, after reading this post you’ll know what to look for and how to prevent mold from growing on your weed.

Effects of Smoking Moldy Weed

Smoking moldy weed is dangerous and in extreme cases can cause death. People with immune system issues, asthma, or respiratory issues are at the greatest risk.

The effects of smoking moldy weed depends on both the type and amount of mold present. The most common effects associated with smoking moldy weed include:

  • Moldy Weed CloseupIncreased trouble breathing
  • Heart palpitations
  • Coughing
  • Diarrhea
  • Vomiting
  • Headaches
  • Aspergilloma – Mold growth in the lungs
  • Pneumonitis – Inflammation of the walls of the alveoli in the lungs

Detecting Moldy Weed

Moldy weed may be hard to detect with the naked eye if it hasn’t had time to spread. When looking for moldy weed you can use a magnifying glass or the 420 scope. If the mold has spread, you may be able to use a black light to look for mold. While under a black light, mold will glow a yellow to greenish-yellow color.

Aspergillus, Penicillium, Rhizopus, and Mucor are the most common types mold you have to look out for and they all look and smell different. Below I’ve listed their characteristics.

Moldy WeedThe Look

  • Black Spots / Spores
  • White to Brown Fuzz
  • White or Black Web-like Material

The Smell

  • Musty
  • Urine
  • Lavender
  • Locker Room Smell

Causes of Moldy Weed

Moldy weed is commonly caused by moisture in combination with the absence of fresh air.

Storing freshly harvested buds that haven’t been cured properly in airtight containers like zip lock bags and jars is a big cause of mold.

Some people like to use orange or lemon peels to add moisture to their dry buds. Using peels can add too much water and may cause blue citrus mold to grow.

Growers and dealers may try to add to their profits by adding water, thus weight, to the weed.

Some people even try to cause certain kinds of mold to grow thinking that this will raise the potency of their pot. Poor growing conditions and growing outdoors is also a source of contamination to mold spores.

Preventing Moldy Weed

Mold survives with weed above a 15% moisture content and will start to breed at 55% relative humidity.

The only way to tell how much moisture is in the air is to test it. You can use a humidity gauge (hygrometer) that’s normally used for cigar humidor or if you are growing marijuana plants you may want to get a relative humidity monitor.

If you’re storing your weed in an airtight container you should “burp” it daily to get fresh air to your buds and prevent mold from growing.

Simply open your jar or bag for at least 15 mins once a day. If your weed gets too dry, use a cigar humidifier to prevent adding too much moisture too fast.

Smoking Moldy Weed

You should throw out any weed that might have mold. But, if you’re desperate there are ways to cut the risk. You can use a bong, but that will only filter out about 15% of the spores.

Baking the weed for 10 mins at 200 degrees fahrenheit will kill most of the mold and prevent it from growing, but it still might cause flu-like symptoms and the mold particulates will still be in your lungs.

Do yourself a favor and just throw it out.

And if you’re looking for more cannabis tutorials to help with storage, check out these posts here.


About Author

Mason is an accredited cannabis aficionado, licensed cannabis retailer, and PhD level guru for all things weed. Originating from California, Mason now lives in Oregon, an amazing place for a cannabis consumer. He consumes cannabis to help him control his insomnia so he can sleep. Mason has grown cannabis, consumed cannabis in many ways, and is an expert joint roller. Mason is here to bring you the best tutorials for anything Cannabis. Whether you are learning how to roll a joint, or looking for the best bongs, we're here to help. Welcome to Cannabis Tutorials, we hope you have a green day:)


  1. i just had moldy weed, it tasted like pepper and smelled like buffalo sauce, very unpleasant and musky and danky and gross and i wish i could wash my lungs now