Humidor humidity and temperature
The range Habanos recommends, why other sources say something different, and what goes wrong when a humidor drifts too wet, too dry or too warm.
A humidor has one job: keep cigars at a steady humidity and a steady, cool temperature. Get both right and cigars smoke well and age gracefully for years. Let either drift and you'll see it in the burn, the wrapper or, worst case, small round holes.
The recommended range
Sources agree on the principle and disagree a little on the numbers.
| Source | Humidity | Temperature |
|---|---|---|
| Habanos S.A. (the leaflet in Habanos boxes says the same) | 65–70% RH | 16–18°C |
| Cigar Aficionado, smoking stock of Cuban cigars | 65–70% RH | 18–21°C |
| Cigar Aficionado, the "70/70" rule of thumb | about 70% RH | about 21°C (70°F) |
| Long-term ageing, as some collectors describe it | 60–65% RH | about 16–18°C |
The real difference is temperature. Habanos sets a ceiling of 18°C; American sources tend to treat about 21°C as ideal. For a collection that's mostly Cuban, the Habanos range is the safer one to follow: it's what the cigars were made for, and it keeps well away from the temperatures at which tobacco beetles hatch.
Within the range, stability matters more than the exact figure. A humidor that holds 66% all year is better than one that swings between 62% and 72%.
Too wet
- Mould. The risk rises as humidity climbs past about 70–72% (sources differ on the threshold).
- Poor burn. Over-humid cigars are hard to light, burn unevenly and can taste sour.
- Split wrappers. The filler and binder swell, and the wrapper can crack.
Mould or plume?
A white bloom on a cigar isn't always bad news.
| Plume (bloom) | Mould | |
|---|---|---|
| Looks | Flat, white, slightly crystalline | Raised, fuzzy or bumpy; may be blue-green |
| Smell | Nothing unusual | Often musty |
| On the foot? | No | It can be |
| What it means | Harmless | Too wet: remove affected cigars and fix the humidity |
Too dry
- Cracked wrappers and crumbling tobacco when you cut.
- A fast, hot burn with little flavour.
- Re-humidify gradually. Bring dry cigars back up slowly rather than all at once, or the wrappers can split as they swell.
Too warm: tobacco beetles
The tobacco beetle (Lasioderma serricorne) is the collector's real enemy. Its eggs can already be in the leaf; warmth and humidity are what hatch them. Published thresholds vary: about 21°C (Simply Cigars), above 22°C with humidity over 72% (Cigar Aficionado), or over 23°C with high humidity (Tobacconist University). Habanos simply says never let a humidor exceed 18°C.
The signs: neat, round pinholes in the wrapper; small heaps of brown dust on the shelf; dust that falls out when you tap a cigar.
What collectors do about it:
- Take everything out of the affected humidor and check every cigar.
- Seal the cigars, or whole boxes, in resealable freezer bags with the air pressed out.
- Freeze them. Sources give about three days (Cigar Aficionado, Tobacconist University, at about −17°C or colder) to four days (Simply Cigars).
- Move the bags to the fridge for a day before returning them to room temperature, still sealed, so the wrappers don't split from the change.
- Clean the empty humidor with a lightly damp cloth, with no cleaning products, and check its temperature before refilling it.
Don't use insecticides anywhere near cigars.
Seasonal drift
Humidity inside a humidor follows the room more than people expect. Indoor heating in winter dries the air, and wood contracts, which can loosen a lid's seal; glass-top and draughty humidors suffer most. Summer brings the opposite risk: warmth. A few habits help:
- Keep the humidor away from radiators, sunny windows and outside walls.
- In winter, check humidity more often, and add humidification if it slips (Boveda suggests more packs or a higher-percentage pack for a leaky humidor).
- In summer, watch the temperature. A cool room or a temperature-controlled cabinet is the answer if it climbs past 18–21°C for long.
Measure it properly
None of this works if the hygrometer is wrong, and many are: cheap digital units can be several points out and dial hygrometers often worse. Test yours before you trust it; our calibration guide shows how. A digital hygrometer that logs readings, such as a Bluetooth sensor, shows trends a single glance can't.
Sources
- Habanos S.A.: Keeping Habanos
- Cigar Aficionado: Collecting Cuban cigars and Fighting tobacco beetles
- Simply Cigars: The tobacco beetle
- Tobacconist University: Tobacco beetle FAQ
- Boveda: humidity and cigar condition
- JR Cigars: mould versus plume
Questions collectors ask
What humidity should a humidor be for Cuban cigars?
Habanos S.A. recommends 65–70% relative humidity at 16–18°C. Many collectors keep Cuban cigars at the lower end, around 65%, because Habanos are tightly rolled and can burn poorly when kept wet.
Is 70/70 right for Cuban cigars?
The 70% humidity and 70°F (about 21°C) rule of thumb is widely quoted, especially in the US. Habanos's own guidance is cooler, at 16–18°C, which also keeps well below the temperatures at which tobacco beetles become active.
What temperature hatches tobacco beetles?
Sources differ: figures from about 21°C to 23°C are quoted, usually together with high humidity. Keeping a humidor at or below 18°C, as Habanos advises, keeps clear of all of them.
Is white powder on a cigar mould?
Not always. Plume (or bloom) is flat, white and slightly crystalline and wipes off; it's harmless. Mould is raised and fuzzy, can be blue-green, may smell musty and can appear on the foot. Plume doesn't form on the foot.