Stogie Guys Free Newsletter

Subscribe today for a chance to win great cigar prizes:


Presented by:

Stogie Tips: Winning the War on Mold

9 Jun 2008

Ask 100 cigar aficionados to name the deadliest predator known to the hobby, and at least 75 of them will identify the dreaded tobacco beetle. That pinhead-sized critter, with its appetite for destruction and its prodigious reproduction rate, is certainly a nasty pest. And just the thought of finding tiny worms boring through your collection of premium smokes is enough to send shivers down your spine.

But there’s a much more insidious – if a bit more prosaic – enemy that is far more likely to devour your stogies. It’s common mold. And if you’re not careful, an outbreak is not just possible; it’s probable.

So how do we know our enemy when we see it? For one thing, mold is almost always going to be a white, green, black, or even blue substance. It’ll smell like mildew – not unlike a dirty gym sock that’s been sitting in the laundry pile for a few days. It will brush off of the cigar when rubbed, but will leave a stain or discoloration in its wake. It will start as small discolorations here and there, but can grow into a thick, fuzzy substance. If the infestation is particularly severe, there might be some mold coating the sides of bottom of your humidor. Mold can spread through both direct contact with an infected stick, or through airborne spores – so it’s easy to see why an outbreak can gradually become a serious issue. If left unmolested, the mold will eat through your sticks and even the cedar lining inside your box.

What’s to be done? The first, and always the best, solution is prevention. Keeping all traces of mold out of your humidor at all times is impossible in certain climates. But you can prevent major outbreaks by keeping humidity levels at the low end of ideal (say, 65-69 RH) and/or never letting humidity climb too much beyond 70 RH (which is good policy anyway). Also make sure that your sticks are getting some air circulation every now and then. If you’re keeping cigars in an airtight container, such as Tupperware, make sure you open the container at least once a month – and preferably more often – to let some fresh air in. Always used distilled water when filling and refilling your humidification devices. Doing so won’t guarantee an end to mold, but it’ll provide much better odds than tapwater.

If you’ve already got some mold in your humidor, assess the extent of the damage before acting. If the mold seems to be localized to just one or two sticks, and if the spots seem small and easily brushed off, simply take those sticks out and plan to smoke them soon. For good measure, sort through your remaining stash for any additional signs of infection. If the mold is widespread – say, coating large portions of individual cigars, or clinging to the walls and floor of your humidor – you need to take more decisive action. First, remove and dispose of the infected cigars; they’re not smokeable and are of no use to you. Next, quarantine the unaffected sticks while you carefully remove the mold from your cedar with a hand vacuum or cloth.

Once the mold is gone, wet the tip of a cloth or Q-tip with isopropyl alcohol, and lightly rub the interior of your humidor to kill off the remaining (invisible) spores. Too much alcohol can damage the cedar lining, so rub/tap lightly and do not drench the cedar. A proper application should dry almost immediately. When it does, rub down the wood (very lightly) with a bit of warm, distilled water. Dry everything very thoroughly, and allow the humidor a few days to air out. During this time you should keep your cigars quarantined before reintroducing them to the humidor. Once the cigars are back in the humidor, monitor everything very closely for a few weeks to make sure no mold has reappeared.

Note that not every whitish coating in your cigars is mold. In fact, a grayish/whitish coating of dust on the skins of your smokes is probably plume (or bloom), an accretion of oils on the wrapper due to age. It’s considered a sign that everything is in good working order, and that your sticks are maturing nicely. Plume will brush off a cigar easily and will not discolor the wrapper; white mold will leave a mark.

Jon N

photo credit: Keepers of the Flame

5 Responses to “Stogie Tips: Winning the War on Mold”

  1. Padronnie Monday, June 9, 2008 at 9:00 am #

    Fortunately (knock on wood), I've never had to deal with this problem.

  2. lucky7 Thursday, June 12, 2008 at 3:51 pm #

    High humidity in combination with high temperatures did me in. As soon as I got the temperature down (to low 70s) I could keep the humidity at 70 without a problem.

  3. Bathed in Smoke Monday, August 4, 2008 at 3:31 pm #

    I would reccomend staying away from isopropyl alcohol as it can sour the cedar. Instead try using a clear ethanol alcohol, preferably one with little to no smell such as everclear or grain vodkas.

  4. Alessandra Wednesday, September 1, 2010 at 7:11 am #

    Great tips, thanks!!

  5. NCF Tuesday, August 28, 2012 at 4:54 pm #

    White mold is not really a problem. Some even claim it enhances the flavours of the cigar, given some time (personally I have never detected any differance in taste). Any other type of mold on the other hand…