Is that mould on my cigar, or plume?
Is that mould on my cigar, or plume?
Mould on a cigar is fuzzy, raised, usually blue-green or grey, spreads in patches and smells musty. Plume is a fine white crystalline dust that sits flat and brushes off cleanly leaving no mark. If it has colour, texture or a smell, treat it as mould and isolate the cigar immediately.
- Mould: fuzzy, coloured, raised, musty, spreads. Plume: flat, white, odourless, wipes off
- Mould takes hold above roughly 72% relative humidity
- Tobacco beetles hatch above about 22°C and leave neat pinholes
- Freezing for 72 hours kills beetle eggs; nothing reverses mould damage
Telling them apart
Plume, sometimes called bloom, is crystallised oil that has migrated to the surface of the wrapper as the cigar ages. It is fine, white or very pale grey, lies flat against the leaf, has no smell, and brushes away with a soft cloth leaving the wrapper unmarked.
Mould is a fungus. It stands proud of the surface, has a fuzzy or web-like texture, is usually blue-green, grey or occasionally white with visible structure, and smells musty. Brushing it off leaves a stain, because the fungus has been feeding on the leaf.
It is worth saying that plume is rarer than the internet suggests, and a good deal of what gets photographed and called plume is white mould. If you are uncertain, assume mould. The cost of being wrong in that direction is one cigar; the cost of being wrong the other way is a humidor.
Is cigar mould dangerous?
Smoking mouldy tobacco is not a good idea. Inhaling fungal spores can cause respiratory irritation, and for anyone with asthma or a compromised immune system the risk is higher. It will also taste unpleasant.
The bigger practical problem is that mould spreads. One affected cigar in a closed humidor will infect its neighbours.
Take the affected cigars out immediately, throw them away, and check every remaining cigar individually. Wipe the humidor interior with a cloth dampened with distilled water — never soap, never alcohol on Spanish cedar — and let it dry fully before bringing the humidity back down to 65-69%.
Tobacco beetles
Lasioderma serricorne, the tobacco beetle, lays eggs in tobacco leaf. The eggs are dormant until the temperature rises above roughly 22°C, at which point they hatch and the larvae eat their way out, leaving neat round pinholes about a millimetre across.
A cigar with pinholes and fine dust in the box has beetles. This is a temperature problem, not a humidity one, which is why a humidor should not sit near a radiator or in direct sun.
If you find them, seal the affected cigars in a bag and freeze them for 72 hours, then move them to the fridge for a day and back to room temperature slowly to avoid cracking the wrappers. Freeze the rest of the box as a precaution and clean the humidor out.
Related questions
The variations of this question people search for most.
Is cigar mould dangerous?
Smoking mouldy cigars can irritate the airways and is best avoided entirely, particularly for anyone with asthma or a weakened immune system. The more immediate problem is that mould spreads to every other cigar in the humidor, so affected cigars should be removed and discarded at once.
How do you tell plume from mould on a cigar?
Plume is flat, white, odourless and brushes off cleanly leaving no mark. Mould is raised and fuzzy, usually blue-green or grey, smells musty and leaves a stain when wiped. If it has colour, texture or a smell, treat it as mould.
Can you save a mouldy cigar?
No. Surface mould can be wiped away but the fungus has already been feeding on the wrapper, and the taste and smell remain. Throw affected cigars away, inspect the rest individually and clean the humidor before there is any question of restocking it.
What causes mould in a humidor?
Humidity above roughly 72%, usually from over-filling a humidification device, adding distilled water too enthusiastically, or a humidor kept somewhere warm with poor air circulation. Keeping the humidor at 65-69% and rotating cigars occasionally prevents almost all of it.