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Cigars/green powder in humador


I just opened my humidor and there is a green powder all aroung cigars and humidor. Looks to be mold are these cigars no good any more? The humidor was high and checked last week no dust. Thanks

Hi Michael,

If the humidity in your humidor was extremely high at any time, it's very possible that the green powder is mold.  To be sure, examine the powder with a microscope or powerful magnifying glass. If substance appears to have long tublar bodies and mushroom cap-like heads, the substance is indeed mold.  If the powder is crystal, stringy or dust-like in appearance, it is most likely plume/bloom.  (Plume/bloom is typically grey or off-white in colour but if you are using an old passive humidifier (with a green foam element), the powder can be greenish or light brown in colour.

Another key sign of cigar mold is that cigar mold grows quickly in thick, random and uneven patches while plume/bloom appears more evenly over a cigar like a layer of dust.

If the substance is definitely mold, it is possible to save your cigars.  To save your cigars and humidor, you will need the following remove all the cigars from your humidor and delicately wipe down each cigar with a paper towel lightly moistened with distilled water.  Delicately wipe down each cigar to remove as much of the green powder as possible. (Cigar mold may leave a discolorated stain on the cigar but don't worry, if properly clean, the stain is harmless).  After wiping down each cigar with distilled water, delicately re-wipe them with a paper towel moistened with isopropyl alcohol.  This will kill all remaining mold spores that remains on the cigar(s).  Delicately re-wipe the cigars with another paper towel moistened with distilled water to dilute the alcohol and then place the cigars in a ziploc bag or tupperware container and place them in your refrigerator for 1 week.  Monitor your cigars closely while they are in your refrigerator.  If mold reappears, repeat the cleaning process.  If mold does not reappear, it is safe to put the cigars back in your humidor.

To clean a humidor and remove it off mold, remove the humidification device and leave the humidor open for 48-72 hours so that the interior can dry out.  Drying out the humidor will loosen the mold particles from the grain of the interior wood and make it easier to clean.  Next, take a vacuum with a soft-bristle attachment and thoroughly vacuum the interior of the humidor.  Next, wipe down the entire humidor interior with a soft, lint-free cloth moistened with isopropyl alcohol.  Do not use too much alcohol.  Use just enough to lightly moisten the wood but not saturate it.  Re-wipe the interior with distilled water and then season the humidor as you normally would. Your humidor is now clean and free of mold.

If you are using an electronic humidifier, wipe the unit down with alcohol, use compressed air to clean the fan/motor and replace the water cartridge.  If you are using a passive humidifier (foam, crystals, bead, gel, etc.), it's best to replace it with a new humidifier.

I hope this helps. If you have any more questions, please feel free to just ask and I will be happy to help.



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James Yee


My main area of expertise is Cuban cigars and I can assist you if you have questions pertaining to Cuban cigars. I can also assist you with the following:

- General cigar-related questions and advice
- Humidor maintenance and troubleshooting (How to treat humidor mold, correct high/low humidity, humidor seasoning, etc.)
- Accessory maintenance and troubleshooting (Cigar cutters, hygrometers, humidifiers, etc.)
- Cigar restoration, preservation and troubleshooting (How to treat cigar mold/tobacco beetles, restoring vintage/dry cigars, etc.)
- Cigar/Brand identification
- Cigar etiquette

Unsure of a certain cigar brand? Wondering what a certain cigar tastes like? Have a question about Cuban cigars? Having problems with a humidor or Just let me know! I have smoked every brand of Cuban cigars and most reputable non-Cuban cigar brands on a regular basis so I know a fair bit about taste profiles, cigar etiquette and other fine nuances to cigar smoking. (NOTE: My main focus is on premium, hand-rolled cigars and not cheap, machine made, convenience store cigars.) IMPORTANT: PLEASE NOTE THAT I DO NOT PROVIDE CIGAR OR CIGAR-RELATED APPRAISALS. If you have a vintage cigar item and you want to know if it's worth something, please contact an antique dealer that specializes in "TOBACCIANA".


I currently have 19 dedicated years of cigar smoking and counting. I have smoked every brand of Cuban cigars and most reputable non-Cuban cigar brands on a regular basis so I know a fair bit about taste profiles, cigar etiquette and other fine nuances to cigar smoking. For 5 years, I studied with Cuban torcedores (rollers), catadores (taste testers) and revisadores (inspectors) on every aspect involving the production of the Cuban cigar and I am currently writing a book that will help beginners understand everything they need to know about cigars and cigar smoking.

Maple Leaf Gardens: Memories & Dreams 1931-1999 (1999; ISBN: 0920445616)
50 Things Every Guy Should Know How To Do (2006; ISBN: 0452286654)
The [London] Times (October 8, 2009)

East York Collegiate Institute University of Toronto

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