Mold, Cigars, Plume & Desktop Humidors

Eco3 Environmental Uncategorized Mold, Cigars, Plume & Desktop Humidors

There are a lot of questions and false information on the internet about mold, plume and how to season a desktop humidor. I’m going to tackle these topics and a few more. This post is definitely geared towards the cigar aficionado. 

Let’s start with the basics. 

When we use the term mold we are referring to fungi/fungus. Here are a few bullet points.

* There are over 100,000 species of mold.

* Mold is not a plant nor is it an animal. 

* Mold spores are the reproductive body of mold similar to seeds. (but not)

* 250,000 spores can fit on the head of a pin.

* Mold spores are everywhere indoors and outdoors in the air we breathe.

* Mycotoxins are a secondary metabolite produced by active mold. (mold odor)

* Mold requires 3 things in order to grow. Oxygen, Water and Organic Material.

* If missing one of the three requirements for continued growth, mold will go into a state of dormancy. Mold can stay dormant indefinitely. 

* Once mold grows it will not die on it’s own, you have to kill it.

Mold is microscopic, opportunistic and does not care about you. It’s nature’s serial killer.

Is it Plume/Bloom or Mold?

This is the question for the ages and I’m about to stick a fork in it!

If you’re not sure if your cigars have mold or plume, it is best not to smoke it and treat as if mold. No cigar is worth the risk.

OK, which camp are you in?

Camp 1 – Plume is mold. You gotta be crazy to smoke it!

Camp 2 – Plume is not mold. Forgetaboutit and smoke it!

Sticking The Fork

I believe plume to be a form of fungal biomineralization. Which is a byproduct of decaying process as this would not occur on a living plant. The science behind fungal biomineralization is fascinating and evolving so the how and why are still unknown. All indicators point to plume being another form of fungus as it exhibits growth patterns as colonization increases.

Some Cigar Experts Say: Some consider a cigar with plume a delicacy and desirable, at it’s best when plume develops. 

What I say: If plume is in fact fungal biomineralization and related to fungal growth, this would indicate the infected wrapper has reached a certain stage of decay. Meaning the wrapper has changed significantly from it’s original state when manufactured. So, smoking a plume cigar would have a different flavor just as dry aged beef has a richer, different flavor. Unfortunately this would also indicate the presence of mold related toxins. 

I would not state smoking a cigar with any amount of plume is considered “safe” 

Do you need a wood humidor?

The short answer is no. If I were in a lab setting, I would never consider keeping anything in a wood container. However we are talking cigars, beautiful cigars which we love. Taking a cigar out of a beautiful humidor is very ritual-like. Opening a well stocked humidor is akin to opening a treasure chest. A nice humidor is not just a box, it’s a compliment to our cigars.

What to do if your humidor/cigars has mold growth?

* Unfortunately the best practice is to remove the contents and throw away the cigars. You cannot save them, consider them to be poison.

* Brushing off the mold will not rid the cigars of mold as the mold is already growing in (not on) the wrapper on a microscopic level. 

* Do not put these cigars into another humidor, you will only infect the new humidor by means of cross contamination. 

Can you clean a mold infected humidor? 

You can with a few considerations. A good quality, recommended product is Benefect Botanical Disinfectant. This is probably one of the best, safest products you can use. It does have a lemon scent which will dissipate over a short period of time. The cost at the date of this post is around $45-$50/gallon. Do not use bleach nor any solvent or chemical. You do not want to use a toxic chemical in a place you store cigars as the chemicals will be absorbed by your cigars.

 Here are a few steps, you must be thorough!

1.  Clean the entire humidor inside and out with a clean, lint-free cloth or tack cloth. Remove everything such as trays, hygrometers, Boveda holders, Velcro etc. Apply the disinfectant by following the instructions on the label. Wear proper PPE. 

2. Treat the items you removed in the same manner. If you have a digital hygrometer with case openings (holes), you must throw it out. Do not keep it!

3. After you treat the humidor, keep the lid open and let it dry naturally. Let the contents dry naturally.

4. Once completely dry, you will take fine sand paper and lightly hand sand the interior and wooden trays to ensure you have removed the mold. This will also freshen-up the surface of the wood so the natural oils are closer to the surface. At this point you should no longer smell the lemon odor from the Benefect. Remove any wood dust with a tack cloth and then used canned air to remove remaining dust from the pores of the wood. 

5. You can now season your humidor (if you choose) and repopulate with cigars.

Note about Cedar: Cedar wood naturally contains mold inhibiting oils. Typically mold won’t grow on cedar especially fresh cut cedar. Cedar laminate or veneer may contain little or no oil due to the  thickness and manufacturing process. Sometimes mold looks like it’s growing on the wood but it is actually growing on organic, microscopic surface debris. White Spanish cedar is typically used in humidors as red cedar tends to be too pungent, affecting the flavor and aroma of cigars.

Seasoning a Humidor

I’m not going to get into whether or not you should season a humidor. I’ll just give you basic advice on how. You will need a new, individually wrapped sponge, gloves and distilled water. Dampen your new sponge with distilled water, put it on a clean dish and put it in the microwave for a few minutes. Please make sure your sponge does not contain metal. The sponge could be very hot so let it cool down before you touch it. Rinse the sponge with the distilled water a few times while squeezing to purge the old water out of it. 

You are now ready to season. Never saturate your humidor, just lightly glide the sponge over the wood in a systematic manner. You will see the moist wood darken a little. Do not apply the water to the point where it forms drips. Don’t forget the interior of the lid and the trays, then close it with your desired humidification device and let it sit for a few days to acclimate. After a few days if the humidity level is where you want it to be, go ahead and repopulate with cigars.

Humidor Placement

Keep your humidor off the floor in a clean, cool area out of the sunlight or anywhere it is subjected to temperature fluctuations. Do not keep a humidor in the basement, not even a finished basement. Typically finished basements are often unhealthier than unfinished basements. 

Should you coat the inside of your humidor with oil, anything?

I do not recommend coating the inside of your humidor with anything. Do not use oils, urethanes, solvents or waxes. Go au natural! If your humidor has a solid cedar interior (not veneer) the natural oils in the wood will help prevent mold growth. Hand sanding with fine sand paper or sanding block followed by wiping with a tack cloth should expose the natural oils that may have dissipated over time.

What is the proper humidification number?

Now this is a topic that I will only touch upon because if you ask 10 experts you will probably get 10 different opinions. Remember, not all tobacco is the same. Some cigars perform better when kept in lower humidity and others in higher humidity. The literature for the Davidoff Zino Platinum Cavern humidor ($3000), states “maintains cigars at perfect humidification of 70-72%”. Davidoff is recommending a higher percentage and Steve Saka is recommending a lower 67% for his cigars and Roma Craft puts a 69% Boveda pillow in their boxes. The consensus for humidity in a humidor containing a variety of cigars seems to be between 65-69%. If you smoke only one cigar, find out what the manufacturer recommends and go from there. 

Keeping Humidity 

Keeping proper humidity has five main considerations. 

1. The volume of space needed to be humidified.

2. How many cigars you have in the humidor.

3. How often you open the lid/door. 

4. The type of humidor. (wood, plastic, etc.)

5. Your specific climate or time of year.

Keeping humidity in your humidor is similar to keeping cold in your fridge. The more you open the lid/door, the more humidity you will lose. How often you open the lid is the one variable you can control. If you open the humidor a few times a day, the humidor may never keep it’s humidity levels depending on the humidification source. If you live in a dry climate, every time you open the lid/door you will loose the humidity in the humidor. Rule of thumb is to only open your humidor as often as needed. 

Your cigars help keep humidification 

Your cigars are like sponges, when they absorb or lose humidity they will expand and contract. Humidity fluctuation is No Bueno for cigar wrappers. 

Well humidified cigars will help regulate the humidity levels in your humidor. If you have a 200 count humidor and only keep 20 cigars in it, chances are you will be fighting to keep humidity and have less humid cigars. Because you regularly open the humidor, the humidor and cigars will absorb and release moisture constantly.

Your humidification source has to be matched to the humidor size.

I prefer to keep a small daily use humidor accompanied by a larger one for bulk single storage. I limit opening the larger humidor to only when necessary. My boxes are stored elsewhere. I use Boveda packs for both humidors and find it keeps the humidity quite well. I do not recommend you reuse/rehydrate the Boveda packs. Also, Boveda packs are not well suited for larger humidors or wineadors as they just don’t have the volume to humidify larger areas. Get a nice Oasis unit or similar. 

Make sure your lid is properly seated and you have a nice tight seal. A good quality humidor will have a slight vacuum/resistance feel when you open the lid. If your lid/door is not making a tight seal, you will not keep humidity. 

Humidor Temperature

Keeping a constant temperature range in you humidor is very important. A cigar will expand and contract with changes in humidity and temperature. On average cigars with a thicker wrapper and binder can withstand these fluctuations while thinner tobacco might not. There are also considerations such as the type of tobacco, and it’s age. Tobacco subjected to fluctuations may develop micro fractures similar to stress fractures. This is why mail order cigars are more prone to having issues than cigars bought from brick and mortar. The more the tobacco is subject to changes and  handled, the more prone they are to damage. Keeping your cigars constantly cool is better than keeping them cold or hot. 

Do you need a cedar wood humidor?

The short answer is no. There are a few really high end humidors made with other wood. Some believe a cedar humidor will transfer an unwanted hint of cedar into a cigar, hence changing the intended profile. For reference, Davidoff makes a non cedar wood humidor. They also make an acrylic humidor. If your cigars were shipped in a cedar box it would seem the manufacturer is fine with their cigars being store in cedar. 

Stop blaming your cigars!

Your cigars are delicate, they depend on you to keep them safe. Improper cigar handling and storage are a factor in a cigar not performing well. Toscano cigars are the exception to the rule!

Most of the time when we experience a poor performing cigar it’s no the cigar’s fault. If you are struggling with cigar performance, reach out to a reputable tobacconist for help. A GOOD tobacconist will ask questions to determine the issue/s and work with you to eliminate possible reasons. 

Don’t assume anything is sterile!

If you decide to buy a new humidor, cooler, sponge, Tupperware or anything to store your cigars, do not assume it is sterile. Did you know the disposable gloves you buy are not considered sterile? Just be safe and do your best to disinfect any storage container before you decide to use it. 


While a tobacconist may not be an expert on mold, a good tobacconist will be able to help you pick a humidor and recommend a humidity level for your cigars. I urge everyone to support your local brick & mortar cigar stores and form relationships with the employees. 

Your feedback and comments are welcome. You are also welcome to email me with your questions. I hope you found this helpful, maybe one day we will share a cigar together!

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