effects of smoking moldy weed

Moldy Weed – Side Effects, Detection, Causes, Protection and Solutions

Nothing ruins dank weed quite like moldy weed that is “dank” in the wrong way. For growers and users alike, having a supply of moldy weed is tantamount to lighting a fistful of cash on fire.

Mold on weed is not only unpleasant to smoke at best and dangerous at worst, but it also can ruin an entire batch of otherwise perfectly good herb.

Below are some tips for avoiding moldy weed mishaps and for keeping both flower and bud perfectly dried without ruining the buzz.

What is Moldy Weed and How to Detect It

For those who know their cannabis strains – the appearance, the smell, the taste – detecting moldy weed is easy.

When smoked, something about the taste of the bud will be off, and if the bud is infected, then the mold might even be visible and/or give off a foul odor.

Marijuana growers should regularly check their plants for mold. Mold on living plants will either appear green and fuzzy or like a white powdery substance on the leaves and shoots. Plants also give off a natural reside, such as with pollen, and this residue can also attract the white powdery mold.

White powdery mold spreads easily, and airborne spores can quickly infect multiple plants, so if any signs of mold are discovered, the infected plant(s) should be removed from the grow tent or room.

When mold infects plants early in the grow process, the spread of the infection can be contained and treated with a fungicide, and the crop can be saved. But for plants that have a heavy amount of mold infestation, the whole plant must be thrown out.

Bud smokers can visibly detect mold on their weed using a 420 scope, a jeweler’s loop, or anything that magnifies the bud for higher visibility.

There are also stash jars with magnifying lids that make it easier to get an up-close look at the herb, whether to check for signs of mold or to admire the bud in general.

Mold on weed will stand out from the sticky hairs and the THC-laden trichomes that look like tiny crystals. The appearance of mold on dried bud can vary, from sticky webbing to white/gray/yellow fuzz, or black or brown spots or spores.

Moldy weed will smell of mildew, or it may give off a rancid odor, almost like urine. Another way to detect moldy weed, although this method is definitely not recommended, is by the flavor. Mold has a distinct, off-putting taste that is easily discernible to the experienced user.


Although it is not recommended, there are times when one can accidentally smoke some moldy weed.

Depending on the extent of the mold infection, the side effects of smoking moldy weed can range widely.


  • Severe coughing/ lung irritation (different from the usual coughing from smoking bud)
  • Tight chest / restricted breathing
  • Chest pains
  • Dizziness or queasiness
  • Headache
  • Bleeding nose
  • Fever

If you think you may have smoked moldy weed, it is best to contact a health care provider.

Although according to the DEA, there are no reported deaths due to marijuana overdose, if there is mold on the bud, smoking moldy weed can have some serious adverse effects.


Mold spores are actually in the air all around us, and when they find an area heavily laden with moisture and a lack of air circulation, they take root and grow.

Mold can spawn and spread in grow rooms with stagnant and humid air. It can also manifest on dry bud when the bud sits in a stash jar that has moisture in it, and that is left capped for enough time for the mold to grow.


There are many steps that growers must take throughout the entire grow process to prevent moldy weed. First and foremost, a grow room must have proper air circulation and controlled humidity levels.

Mold grows best in wet, humid environments with stagnant air, so it is important to make sure that humidity levels are maintained, both in humid and dry climates, and fans or ventilation systems should be in place to keep the air fresh while using full spectrum grow lights.

For more information on maintaining humidity levels in a grow room, check out this video.

The drying and curing process is also crucial for preventing mold. Once the flower has been harvested and the plant is ready to be dried and cured, the timing and the method of drying can affect the plant’s vulnerability to mold exposure.

If the drying process is too lengthy, then mold can develop. On the other hand, if the plant is dried too much, then the bud will be harsh to smoke. When drying weed, humidity levels in the room should be around 50% with room temperatures of around 70°F.

For the curing process, when curing in jars, the humidity levels should be around 60-65% with room temperatures around 70°F. Throughout the curing process, it is also important to open the curing containers regularly to allow air circulation.

Bud smokers can protect their herb from mold through proper storage. Using plastic bags to store weed is not recommended because they trap moisture.

There are plenty of different types of stash gear, like glass jars, mini tins and boxes, or beautifully carved wooden boxes, for storing weed in optimal environments. Hygrometers not only function as elegant stash boxes, but they also control humidity levels within the container.

What to do with moldy weed

Unfortunately, there is not much that can be done with moldy weed aside from throwing it out. Growers who detect moldy weed at an early enough stage can treat and eliminate mold with fungicides.

For users, moldy weed can be smoked with certain methods – such as with bongs, or cooking the weed at 200°F for ten minutes, or super critical extraction – but none of these fully eliminate mold.

On a positive note, in states where marijuana is legal for medical or recreational use, dispensaries put their products through rigorous testing and inspection processes, so the risk of moldy weed is low.

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Moldy Weed – Side Effects, Detection, Causes, Protection and Solutions Nothing ruins dank weed quite like moldy weed that is “dank” in the wrong way. For growers and users alike, having a supply

Stoner Alert: Smoking Moldy Cannabis

“Damn you! Damn you, you filthy mold!” You don’t want to scream this barechested on your knees before a cannabis garden ravaged by mold. Weed mold is no joke for stoners and this article just might save your life one terrible day.


We don’t mean to be alarmist, but in our opinion, moldy weed is public enemy #1. Of all the pests, plagues, rotten bad luck and scourges of Mother Nature, that can possibly strike a marijuana garden, it’s cannabis mold, that’s the most heartbreaking and toxic threat to the ordinary decent stoner.

Moldy weed is not just a horrible excuse for a stash, it’s actually toxic waste and you should treat it as such. If you have the misfortune to consume moldy weed, regardless of whether you eat it, smoke it, or vape it, you are consuming thousands, possibly tens of thousands of nasty microbial spores.

Best case scenario is the unpleasant taste puts you off consuming much and you toss the rest of the contaminated weed stash in the trash, post-haste, without any ill effects.

Worst case scenario is you wind up hospitalised with a serious lung infection and your only frequent visitor is a slimy anti-marijuana lobbyist intent on getting the rights to the story of the first recorded cannabis death in history. Even if she/he must finish the job themselves, probably with a pillow during the brief interval of nurse shift change.


If you happen to be purchasing your stash from a reputable cannabis club, coffee shop or your marijuana dispensary, then you really shouldn’t have to worry about moldy weed. But unfortunately, you do, because mold does not discriminate between amateurs and professionals, all it requires is optimal conditions, even post harvest.

A botched curing job or improper storage by the cannabis retailer can turn a Kilner jar full of weed into a furry mess of fungus. Wet weed is a breeding ground for fungus and an invitation for mold.

Even after a slow and careful drying, ideally, in simple brown paper bags, curing is the final step and too often where it all goes terribly wrong.

Another unpleasant characteristic of moldy weed is its mildew-like smell. Sometimes it can be more like hay, but something is always off with the scent of moldy bud. It pays to give your potential stash a whiff as well as the initial eyeball inspection.

Most high-end cannabis retail operators are not too keen on the customers getting overly touchy feely with the weed menu.

Only and we really mean only if it’s kosher with the budtender, it’s best to sample a spliff or a pipe hit, providing a full hands-on touch and taste test is permissible. If you get the green light, always go for it, the best hits are free hits anyway.


We have seen too many YouTube videos of growers stuffing untrimmed or minimally trimmed freshly harvested plant material directly into glass jars. This is a huge mistake and definitely not to be imitated. Well manicured bud is also less susceptible to mold as stems and leaves can retain a lot of moisture.

Essentially humidity is the harvester’s enemy, but also a necessary evil, because too low relative humidity leads to crumbly, overdry nuggs, that are probably mold free. Although they won’t be quite as tasty as they could have been if the RH had been kept in the sweet spots (30-50% for drying and 55-65% for curing).

Moldy weed will usually display a white-grey candyfloss-like fungal growth covering the exterior of buds or alternatively if the stem has rot a trophy cola literally from the inside out, giving you a disgusting surprise when you break her open. Molds can come in all kinds of colours and the worst fungal infestations can turn buds into brownish sludge.

Cannabis cultivators can encounter bud mold in the garden at any stage and it is usually due to a combination of problems in the grow show. Leaves and stems with early warning signs of mold cannot be ignored. A foul rotting and/or mildew-like smell will be noticeable.

Growers are advised to invest in a pocket microscope. They are not only handy for zooming in on resin, but a great way to detect pathogens being hosted by your cannabis plants. It might make for a horrific sight, but you can’t even begin to fight an unseen enemy. Early diagnosis gives the grower a fighting chance to save the cannabis garden.

Removal of infected plants is a necessary sacrifice for the greater good of the ganja crop. Patient zero has got to go if a full blown mold pandemic is to be averted. Maintaining optimal environmental conditions and not overwatering or otherwise stressing plants is the best preventative remedy.


Just one mold-plagued plant has the potential to contaminate your entire grow op. Absolutely everything from the rest of your plants to the growing medium and containers. If you’re growing indoors, the grow room or grow tent will require a thorough cleaning to ensure no spores survive to infest the next crop.

It’s a nightmare scenario, you can try to fight with various anti-mold agents, but the plant casualty rate will be unacceptably high in any case. Moldy weed is a threat the diligent cannabis cultivator must watch out for at every stage from seed to spliff.

Moldy weed is garbage and no stoner should dare to knowingly consume it in any form. Equally, no cultivator or ganjapreneur should knowingly trade in moldy weed. 100% guaranteed reputation wrecker.

Stoners need to avoid polluted stash at all costs and by performing a few routine inspections of weed you can at least confirm if it’s clean or not before you part with your cash.

Of course, we recommend you grow your own fine organic herb, adding some liquid silica to toughen plants up and always use aerated, well draining premium quality substrate.

Mold is the highest level threat to a fine weed stash. Moldy weed is not stash, it's trash and can even be a health hazard. Lets talk about contamination.