Cigar 101: An Age Old Controversy Plume Vs. Mold – By Mike Holmes

Earlier this year I wrote an article about setting up and maintaining your humidor in which I briefly touched on avoiding mold in your humidor. I purposely did not mention the Mold Vs. Plume argument because it is a subject in itself, which deserves its own article. The Mold Vs. Plume argument isn’t a very complicated subject, but because there is a lot of misinformation and misunderstanding on this subject it is and has been one of the top controversies in the cigar community for a very long time.

I am going to tackle this article from several different angles, first by explaining why plume isn’t a myth and also by explaining exactly what plume and mold actually are. My hope in writing this article is that you will walk away from reading it with a deeper understanding while hopefully relieving any confusion on this subject. I am not an expert by any means, nor do I claim that this will be the greatest plume vs. mold dissertation, however I am confident that I will help to put to rest a lot of the misconceptions on this subject. Now let’s begin….

Is Plume a myth?

Upon researching for this article I ran across a few different stances on the matter. It is safe to say, there is a segment of the cigar smoking community that believes plume is a myth. Those that claim this may have come to their conclusion because of a study done by Friends Of Habanos who conducted a study with a lab called “Australia Biotech Laboratories”. The study tested 10 cigars and in each lot they found different types of mold on the different cigars that were believed to be plume. There were 4 different types of mold found on the different cigars. I am quoting each different type of mold found below,  there were a few of the same cigar used that is why it only counts out to 8 cigars. 

(Romeo y Julieta Millie Fleurs)

Candida parapsilosis-

 “a fungal species of the yeast family that has become a significant cause of sepsis and of wound and tissue infections in immuno-compromised patients. The immune system is a major player in Candida parapsilosis infections. Candida parapsilosis is not an exclusive human pathogen, having been isolated from nonhuman sources such as domestic animals, insects or soil. Candida parapsilosis is a normal human biological relation and it is one of the fungi most frequently isolated from the human hands.”


(Bolivar No. 2)/Diplomatico No. 2)

Penicillium ascomycetous-

Penicillium ascomycetous fungi is of major importance in the natural environment as well as food and drug production. Some members of the genus produce penicillin, a molecule that is used as an antibiotic, which kills or stops the growth of certain kinds of bacteria inside the body. Other species are used in cheese-making. According to the Dictionary of the Fungi (10th edition, 2008), the widespread genus contains over 300 species.


(Partagas Lonsdale)/ (Por Larranaga Petit Corona)/ (Hoyo de Monterrey Epicure Especial)


defined as a group of conidial fungi – that is, fungi in an asexual state. Members of the genus possess the ability to grow where a high osmotic concentration (high sugar, salt, etc.) exists. Aspergillus species are highly aerobic and are found in almost all oxygen-rich environments, where they commonly grow as moulds on the surface of a substrate, because of the high oxygen tension. Commonly, fungi grow on carbon-rich substrates like monosaccharides (such as glucose) and polysaccharides (such as amylose). Aspergillus species are common contaminants of starchy foods (such as bread and potatoes), and grow in or on many plants and trees. In addition to growth on carbon sources, many species of Aspergillus demonstrate oligotrophy where they can grow in nutrient-depleted environments, or environments with a complete lack of key nutrients.


( H Upmann Magnum 50)/ (Montecristo no.4) 

Wallemia sebi

Wallemia sebi is a dry fungus of the phylum Basidiomycota. It is commonly found on highly sugared or salted materials, such as jams, bread, cakes, sugar, bacon, salted meets, and salted fish. It is also found in indoor air, house dust, and soil. One distinctive feature of W. sebi is its relationship with water activity. Most fungi are profoundly affected by the availability of water. The ability to tolerate environments with low water activity has been found mostly in Ascomycota, but rarely in Basidiomycota. However, W. sebi. can adjust its morphology and physiology to adapt to different environmental conditions and survive osmotic stress. Wallemia sebi have lower limits for growth below water activity of 0.75aw (water activity), while most microorganisms are limited to 0.95 and above. Wallemia sebi has been isolated from hair, hay, textiles and man. It can grow slowly without additional solute in the growth medium, and form small, reddish-brown, powdery colonies.


Unfortunately, people are taking the results of this particular study and using it to back up their stance on plume being a myth, which causes confusion for the consumer. The study does not come to the conclusion that plume is a myth. Friends of Habanos simply asked people to send them cigars that were believed to have plume, for store credit, and they would send the cigars to the lab to test and verify if it was plume or mold. In this day and age it is fairly easy to take a small tidbit of information to use in backing up a personal opinion.

Plume is Not Made Up

There has also been online rumors spread through various cigar forums and Reddit groups, that the cigar industry created the myth of plume to sell more cigars. I personally find that to be silly, but the internet is a wild place filled with every type of fantasy known to man! The truth is, every person in the cigar industry that you talk to would agree that plume is in fact not a myth, but is a natural occurrence. Plume is scientific and is the result of cigars being stored in absolutely perfect conditions. Tobacco is alive, so even after a cigar is in its final form, the leaf continues to live, although it is no longer in the ground attached to the plant. Changes will occur if kept in optimal conditions which result in oils rising to the surface of the wrapper and crystallizing. That is what we call plume. Essentially plume is a chemical reaction to the perfect resting  environment.

It is unreasonable to equate plume to being mold and accusing the cigar industry of making up the idea of plume in order to sell cigars that have slight mold on them. I simply found no data backing up the notion that plume is mold or that plume is a myth. Every major cigar publication I have read while researching this has agreed with my stance on plume. I am not the biggest scientific minded person, so I apologize if my findings aren’t deep enough. Due to consistency in what I read, I find it hard to believe that plume is a myth or a made up faction of the cigar industry. Plume is simply an indication of a cigar stored in perfect conditions nothing more, nothing less. 

What is Plume? 

Plume or “Bloom” is a light dust that appears to crystallize. Plume covers the entire body of the cigar, and is white or light gray in color. Plume develops when cigars are kept in perfect conditions; usually between 69-73 percent humidity. When a cigar ages in perfect conditions for long periods of time, the natural oils from within the cigar rise to the surface and crystallize resulting in plume.

Plume is a very good sign of a well aged cigar and also a very welcomed treat! Plume does not necessarily improve the flavors in a cigar, but there is nothing better than smoking a cigar that has been kept in optimal conditions. Although plume isn’t necessarily going to improve notes you get from the cigar, a well aged cigar might mellow out some and create a smoother smoking experience. Of course, this all depends on the types of tobacco used and from which region. Normally, stronger oily wrappers will develop plume. With that said, different tobaccos react differently over time and that is the beauty of cigars. Sometimes it is hard to tell how age will affect a cigar, but like wine, over time they always get better!

To sum it up, plume is good and should be a welcome sign and an indication of your cigars being stored in optimal conditions. Below are a few examples of plume so that you can see for yourself exactly how plume looks so there won’t be any confusion with mold. Which brings me to my next question….

Plume – Photo Courtesy of

What is mold? 

Now that you know what plume is, with clear distinctions, I will now tell you what mold is! 

Mold is not good. Having cigars with mold on them is a sign that your cigars have not been kept in optimal conditions. If your humidor has too much moisture from humidity, it won’t be long before your prized stash develops mold. Mold is normally found around the foot of a cigar but can be anywhere on a cigar and can be white, blue or green. I have read that if the mold is white you can still smoke that cigar, but my personal opinion is, you shouldn’t smoke any moldy cigar! I say this because mold is a sign of a cigar being kept in less than optimal conditions, so it isn’t a good idea to smoke a cigar that is kept in inadequate conditions.

Cigar Mold – Photo Courtesy of

The best indicator of a cigar having mold is a simple test. Mold does not wipe off as easily like plume does! The mold embeds into the leaf. Cigars are no different than any other object that can grow mold. Cigars kept in an environment that is too moist will surely develop mold. By now I know you are wondering, “What should I do if I find mold on any of my cigars?” The first thing you should do is determine if all or just some of your cigars have been affected by mold. Separate the cigars that have obviously been affected and dispose of them. After all the affected cigars are disposed of, mix a little rubbing alcohol with distilled water and wipe down your humidor. DO NOT soak it, just wipe enough to kill any mold and leave your humidor open to dry for a few days. Once your humidor is dry just re season your humidor making sure the temperature and humidity inside it is within the perfect conditions to avoid any future mold problems.

In Conclusion

I realize that no matter what is said on this subject there be people who will still hold to the same opinion. My goal for this article was to make the topic a little less confusing while giving everyone something to think about. What we can all take away from this is that the plume vs. mold debate is not as complicated as people make it out to be. All it takes is a little common sense to understand the issue. Regardless of where you stand, we can agree that we ALL want to smoke our cigars in pristine condition and not worry about the unnecessary bullshit that life throws at us. Pssita (put some smoke in the air) to my cigar family worldwide! Also comment below if you want to discuss this topic further.   

51 thoughts on “Cigar 101: An Age Old Controversy Plume Vs. Mold – By Mike Holmes

  • Great article the General rule I follow is 70 percent humidity and the temperature of 70 and really works well for me.

  • thanks for reading Patrick i always appreciate your comments and stogie press support!!

  • I’m sorry to say that is mold bro. Seriously that poor Unicos deserved better. Plume is a real thing but you are showing these people a clear picture of mold.

    • I am an environmental engineer of 30 + years. A patent holder, inventor, and an expert in the areas of water purification, contamination, and general biology, physics and chemistry.

      Let me end the debate for you.

      Molds are alive. Using sterile technique, I placed plume scrapings from 5 different cigars, inoculated 3 different Petri dishes filled with beef agar, and incubated the dishes/plates for 7 days. Not one of the Petri dishes showed any growth at all.

      In addition, my lab has both an Atomic Absorption Mass Spectrophotometer, and a Gas Chromatograph. By multiple comparative analyses, Plume was shown not to be mold.

      I don’t know what your expertise is, but my comments are based in accurate and specific testing.

      • Tom,

        This is excellent feedback. Maybe i should have You on my show Taking it to the Nub. You can explain this to the naysayers and talk through your research it would be a very informative show. I’ll leave that up to you. Thanks for following stogie press.

        Regards Jimmie

  • It’s sad when cigar media, who have a responsibility to this hobby, and who theoretically are more knowledgeable than the average smoker, repeat old wives’ Tales like this.

    The FOH study tested DOZENS of cigars. From people who thought they had what looked like “plume.” Every one of them was a form of mold.

    You say it’s “crystallized oils” — PROVE IT.

    You say it forms when cigars a stored perfectly — PROVE IT.

    You say “plume” is not made up — PROVE IT.

    You’re a misinformed, low-information smoker masquerading as a knowledge base. And you are spreading lies.

    You knew what you were wading into when you tackled this subject. And you’ll reap the consequences. Now those smokers who know a thing or 2 will stop reading your articles.

  • All somebody had to do is take their so called “plumed cigar” to any qualified microbiologist and they will say whether it not it’s mold. They study pretty much 90% mold spores when learning to be a microbiologist so they’re qualified to make that identification.

    The myth of plume has been about with many cases that they have plumed cigars yet not one proven evidential case to bring the aficionados.

    It’s mold guys just accept it. Science states even if it was to be crystallised oil it wouldn’t change flavour it would just indicate a well aged cigar. Well whooptydoo I have many well aged and beautiful cigars and I don’t need plume to tell me.


  • Gentlemen, gentlemen, I beg your pardon, but I believe y’all are wrong if you think what is on that Tatuaje is mold or plume for that matter. It appears to be colonies of bacteria…

  • Great article Jimmie. Notwithstanding the comments. Mold and plume are different, with different causes you clearly lay out,

    • What was clear about what he “laid out”? He repeated unproven claims that have been repeated ad nausem by people who don’t know. The FOH study is the only acientific study ever done on this, and it clearly point to mold. Every time.

      And that Tatuaje… is a health hazard.

      • Exactly!! I read the article looking for some kind of prove able counter point to the all plume is mold position, but there isn’t anything in this article that counter the facts provided by the FOH study.

  • Article is well written, however mold doesn’t exist. It was proven multiple times in the FOH study. Show an actual close up picture of what you call “plume” under a miscroscope and you’ll see it’s not what you think it is. It is ALWAYS mold

  • Even by the loosest standards (a thin, even, crystalline coating), the example of ‘plume’ you’ve shown is blatantly mold. For the sake of your credibility, please fine a better photo (preferably a photo of a cigar that has been lab-tested and plume confirmed, but at very least, one that passes the standard visual checklist).

  • My name is Jenna, I’m a biologist with a focus on botany, who also smokes cigars with my husband (also a biologist). We happened upon your article and wanted to let you and your readers know how utterly misinformed you are. Your assertion that tobacco leaves are still alive after being picked from the fields, dried and fermented is the equivalent of saying that a cow after being slaughtered, carved and made into beef jerky is still alive. Additionally, in the drying and fermenting process, the moisture content of the leaves is greatly decreased. This dry state of the tobacco leaf as well as its hydroscopic nature will actually absorb moisture and oils that it comes in contact with. Your unsubstantiated claim that oil will rise to the surface is actually the complete opposite of what would happen, particularly in a humidified environment. The only way for a cigar to loose moisture and oils is if the environment it is in is drier than the tobacco itself. Due to the fact that the tobacco is dried and fermented prior to being rolled the chances of any moisture or oil coming to the surface in a humidified (according to you 69-73% RH) environment is non-existent. You clearly have no understanding of what you are writing about and less about plant biology. Please do not write articles with false notions. At best this is an opinion piece constructed by a poorly informed individual.

      • Lol. Is that seriously your only argument against such a well written comment backed by science?
        If you’re trying to debunk her, the least you can do is TRY.

      • Attacking a single grammatical error and not addressing any of the facts being presented. Good job, nobody is going to believe her comment now.

  • The foh study had lab results and evidence. This is all “I know because I know”… prove it. They tested way more than 10 cigars, keep reading the thread. Dont show me a picture of plume and not test it. Without backing it up, this is sensational misinformation. That tat is mold 100%, show me the lab results.

  • This never gets old. It’s the same old BS that keeps getting regurgitated over and over. 10 out of 10 times it’s mold.

    • Yes.. *BUT*… What about the 1 time out of 10 that it is plume? So… 11/10 times it is either plume or mold–and I think we can agree here that my math is sound–that’s 110%, which is exactly how much coach said to give, and exactly the level of gumption the author has brought to this article. (The extra 10% = BS)

  • Boston Jimmie here – I want to thank everyone who has commented on this article. I feel it proved it’s point – mold vs plume is the most controversial topic in the cigar community. I purposely used the Tatajue cigar photo as an example of plume and it got the reaction I expected. Those that believe plume is real and those that believe it is not stated without testing that it is mold. Of course those that don’t believe in plume any such material is mold but those that do believe in plume- how can you say what it is if you don’t have the physical cigar in you hands? In the end use your own judgment and smoke what pleases you.

    • “how can you say what it is if you don’t have the physical cigar in you hands? In the end use your own judgment”

      No dude, don’t use your own judgment. Use SCIENCE. There are ZERO studies demonstrating evidence of plume, and at least one study that demonstrates evidence against it. Proof is actually proof, so provide some proof of plume please.

    • Jimmie, you are entitled to your own opinions. But you are not entitled to your own facts. Your argument about “belief” is pure Trumpistan bullshit. Facts are facts, and mold is mold. And “plume” is mold. And you are mold.

      • Yea I am a “plumer” ? only three times in my 39 years of smoking cigars have I found what I feel is plume on a cigar- and yes I smoked those three cigars. No effect no impact.

  • Holy fuck this is the absolute dumbest piece of shit article I’ve ever read. Please, genius, just give us ONE link to a source that shows any evidence at all that plume exits. Just…one…please.

  • Total malarkey.
    Plume is either mold (99.9%) or dust (.1%)
    If you want to smoke it knock yourself out. Enjoy the steeply increased risk of emphysema and COPD. While It’s true, we inhale mold with every breath, and there are over 4 million different types of mold catalogued to date and counting, repeated and direct contact with colonies that large will undoubtedly increase the risks to your health exponentially. Please done risk your lungs more because it makes you feel fancy. Play it safe and demand that your tobacconist supplies you with cigars that don’t require a chemistry set to prove their safe. “That’s mold bro!”

  • You’re going to tell us plume exists because “science,” despite the only scientific study cited disproving your claim? I understand the FOH study was VERY limited, but where is the study proving its existence? Perhaps before masquerading your OPINION about the existence of plume as fact, you should find some supporting documentation… other than a photo of another moldy cigar. If you have access to one, stick it under a microscope and SHOW US!

    Seriously, you should be ashamed of drawing this conclusion based only on “everyone in the cigar industry agrees with my stance.” 40 years ago, everybody in the industry would also tell you tobacco does not cause cancer. “Everyone” can be, and are quite often wrong.

  • I have been colander smoking for 35 years. I have plenty of cigars covered in crystals and love well aged cigars , I believe all cigars have mold on them and in some cases it blooms and if you lucky you can wipe if off and still enjoy the cigar
    The picture you are showing as a example of plumbe is mold imho

  • Cigars are not like a fine wine. They do not get better with age. At a certain point in the aging process, they begin to also lose flavor. Yes they mellow, but also experience loss of flavor.

  • I thought they were going to change the picture of the moldy cigar to a picture of one with “plume”. Must still be searching the internet to find one….hmmmmmm.

    • Note my comment below.. why I chose that picture – without actually holding that in your hand you can’t make a judgment and then that is only if you are a “plumer” which by the way, most cigar smokers are not it seems. So the debate goes on….

      • But judging by the fact I can see the blotchy patches AND hairlike appearance in certain spots, it’s obviously mold without me having to hold it in my hand

  • That Tat is not plume, that’s nothing but mold. Plume is like Bigfoot, everyone says it exists but there is no clear evidence of it. All examples have been disproven.

    • Well, let’s say “certain types of people” say Bigfoot exists. Not everyone, surely. But there is a type who is, let’s say, more easy to persuade that conspiracies are true.

  • – Being in the cigar industry for over 20 years, and visiting alot of different humidors, I’ve seen all types of eye popping samples. Most of all the walk-in humidor with the jet engine humidification that blasts this steam looking humidity. They use tap water and filters, not the suggested distilled water…I truly believe the water vapor lands on the cigar and dries, leaving behind a dusty looking powder. Harder (higher mineral, metal content) the water, more dust left behind as the water dries. And some cigars have only been in there a month or two. This plume that is spoken of really has nothing to do with age. It’s on the cello, and on cigars that are not in cello. Surely the cello is not producing “crystallized” oils….
    Full disclosure; I was once a believer of plume, because the very first shop I worked at, the owner insisted it was plume, on a very well aged cigar…………. Now I believe there maybe a dust that forms on a well aged cigar, visible better on dark wrappers. But like a writer prior to me…99 out of a 100 is mold. 1 is dust.

  • I’m glad to see the vast majority of people here are smart enough to realize it’s all mold. It gives me faith in our great community.
    This article is getting very bad press and rightly so. smh.

    • Actually there is no such thing as bad press. In fact it is encouraging that so many have read and commented on the article. I agree that the vast majority of cigar enthusiasts do not subscribe to the plume theory as shown in the comments. Thanks for reading and contributing.

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