Guide
Cigar beetles, mold or plume, dry cigars: what to do
8 min read
Three things go wrong in a humidor: beetles, mold and dryness. All three come from temperature or humidity drifting out of range, and all three can usually be stopped if you catch them early. Here is how to recognise each one and what to do.
Cigar beetles
The tobacco beetle (Lasioderma serricorne) is a small, reddish-brown beetle of 2–3 mm. Its eggs can be present in tobacco from the field and hatch when the temperature stays above about 24 °C (75 °F), especially together with high humidity. The larvae eat through the tobacco and the adult beetles bore out.
Signs of beetles
- Pinholes about 1 mm across in the wrapper, often straight through the cigar
- Fine tobacco dust under the cigars or on the bottom of the humidor
- Tunnels inside the cigar when you cut or break it open
- Small beetles in the box or, at worst, flying around the room
What to do
- Isolate the humidor. Take everything out and check every cigar. Discard those with holes; one beetle can lay a hundred eggs.
- Freeze the remaining cigars. Put them in a zip-lock bag (press out the air), then into a second bag or an airtight box. Leave them in the refrigerator for a day, then the freezer for three days at -18 °C (0 °F) or colder, then the refrigerator for another day before room temperature. The slow change keeps the wrappers from cracking and condensation from forming.
- Clean the humidor. Vacuum it thoroughly, including the corners and under trays, and wipe it with a barely damp cloth. Do not use insecticides.
- Fix the cause. Keep the humidor below about 21 °C (70 °F), away from sun and radiators. A cooler room or a thermoelectric cabinet solves summer heat.
Many collectors freeze every new box as a precaution before it goes into the humidor. It does not harm the cigars if the temperature is changed slowly as above.
Mold or plume?
Both appear as a coating on the wrapper, and the difference matters: plume is harmless, mold spreads and ruins cigars.
| Sign | Mold | Plume (bloom) |
|---|---|---|
| Colour | Blue, green, yellow, sometimes fuzzy white | Fine white or greyish, like frost |
| Texture | Fuzzy, three-dimensional, grows into the leaf | Flat, powdery crystals on the surface |
| Where | Often at the foot, in the cap, on the cut and on the wood | Evenly over the wrapper |
| Wipe test | Smears or stains, comes back | Brushes off cleanly with a soft brush |
| Smell | Musty, damp | Nothing unusual |
Colour
- Mold
- Blue, green, yellow, sometimes fuzzy white
- Plume (bloom)
- Fine white or greyish, like frost
Texture
- Mold
- Fuzzy, three-dimensional, grows into the leaf
- Plume (bloom)
- Flat, powdery crystals on the surface
Where
- Mold
- Often at the foot, in the cap, on the cut and on the wood
- Plume (bloom)
- Evenly over the wrapper
Wipe test
- Mold
- Smears or stains, comes back
- Plume (bloom)
- Brushes off cleanly with a soft brush
Smell
- Mold
- Musty, damp
- Plume (bloom)
- Nothing unusual
True plume, crystallised oils from slow ageing, is rare; most white “plume” people find is in fact mold. If you are unsure, treat it as mold.
What to do about mold
- Remove the affected cigars and inspect the others. Light surface mold on the wrapper can be brushed off outdoors; cigars with mold at the foot, in the cut or inside should go.
- Lower the humidity. Mold grows above about 72–75 %. Replace the humidifier with two-way packs at 65 % or 69 %.
- Clean the humidor. Wipe the wood with a cloth barely dampened with distilled water and a little vinegar, air it for a day, then season it again. Mold that has grown into the wood may need a light sanding.
- Recalibrate the hygrometer. A humidor with mold is almost always more humid than its hygrometer says.
Dry cigars
A dry cigar crackles when squeezed gently, feels light and hard, and burns hot and fast with a harsh, papery taste. The wrapper may already be cracked. Dry cigars can be saved if you go slowly: rehumidifying fast makes the filler swell and splits the wrapper.
- Start low. Put the cigars in a zip-lock bag or tupperdor with a 62 % two-way pack. Leave the cellophane on if they have it; it slows the process down, which is what you want.
- Step up after a week. Move them to 65 %, and after another week to your normal level, 65–69 %.
- Rotate them every few days so they take up moisture evenly.
- Give it time. Two to four weeks for cigars that were dry for weeks; longer for ones dry for months.
Very dry cigars, kept for months in a warm room, often lose oils and aroma for good. They will smoke again, just not as well as they once did.
Prevention is a weekly glance
All three problems start with humidity or temperature drifting. Keep the humidor at 65–70 % and below 21 °C (70 °F), calibrate the hygrometer twice a year and look at the cigars once a week. How to store cigars and how to season a humidor cover the setup; the humidor calculator checks your conditions. With aficio you know what is in your humidor, how many of each and when you bought them, which makes a quick check and a clean-up much easier.
Questions
- How do I know if my cigars have beetles?
- Look for pinholes about 1 mm wide in the wrapper, fine tobacco dust under the cigars and tunnels inside a cut cigar. Small reddish-brown beetles in the box confirm it.
- Does freezing cigars kill beetles?
- Yes. Three days at -18 °C (0 °F) or colder kills eggs, larvae and adults. Double-bag the cigars and move them through the refrigerator for a day on the way in and out, so they do not crack or collect condensation.
- How can you tell mold from plume on a cigar?
- Mold is blue, green or fuzzy white, grows into the leaf, often starts at the foot and smells musty. Plume is a flat, even, white powder that brushes off cleanly. When unsure, treat it as mold.
- How do you rehumidify dry cigars?
- Slowly. Seal them in a bag or tupperdor with a 62 % humidity pack for a week, then move up to 65 % and later to your normal level. Fast rehumidifying cracks the wrapper.