Many cigar enthusiasts are quite surprised when they go to check on a batch of cigars only to find that mold has somehow managed to enter the humidor and accumulate on the trays or the cigars themselves. This leads to the question “what causes mold in a humidor?” and the answer is a bit tricky. This is because there are actually a few valid reasons that mold might appear.

Let’s first look at the conditions in the humidor and then address the ways that this could lead to mold. Firstly, what is the correct environment for storing cigars? Usually it is the same sort of environment in which tobacco is originally grown - hot and humid. The traditional “formula” for the interior of the box is the 70/70 approach. This is a relative humidity of 70-75% and a steady ambient temperature of 70 degrees Fahrenheit. So, right here we have something that describes the ideal conditions for mold growth, but there are a few reasons that such a thing tends to not occur.

The first common problem is the water inside of the box. More often than not this water is managed by a humidifier. The humidifier can be attached to any area of the interior of the box, but it can also often become blocked by too many cigars or by a tray without any slats for aeration. This leads to an over accumulation of water in a single area, which could mean that cigars are soaking wet or that the wood of the trays is saturated. This will then lead to mold, especially if the box is not opened on a regular basis.

If water is not the culprit, it is usually bacteria on the trays or the cigars themselves. Like many other activities in life, it is best to thoroughly wash the hands before opening and handling cigars. If not, the oils, bacteria, or even the dirt and food residue which cannot be seen by the eye can find a home on the surface of the object and then begin to thrive in the dark, warm and moist conditions of the humidor.

What can be done about this? There are several proscribed methods for treating contaminated cigars, but where the interior of the box is concerned the best approach is to remove the cigars and the humidifier and wipe the entire surface with Isopropyl Alcohol. This will be quickly absorbed by the still humid cedar wood of the lining and it will quickly destroy any remaining mold spores.

Ryder is a consultant for an online specialty butane lighter store and has expert knowledge of cigar accessories, including where to buy zippo lighters.