A drying room (or drying tent) is any space set aside to dry harvested cannabis. The goal is to remove water slowly and evenly, without mould and without driving off volatile terpenes, before the buds go into curing containers.
In practice
Common targets (Grower practice, aligned with post-harvest benchmarks and drying research):
| Factor | Target |
|---|---|
| Temperature | about 15-21 °C (60-70 °F) |
| Relative humidity | about 55-62% |
| Light | darkness |
| Air | gentle circulation around, not onto, the buds; slow exchange |
| Duration | about 7-14 days |
Equipment is usually a small dehumidifier or humidifier, a fan aimed at a wall or the floor, a carbon filter for odour, and a calibrated hygrometer at bud level.
Warm, dry rooms dry too fast and give a grassy, hay-like smell, harsh smoke and terpene loss. Cold, damp rooms risk mould. The dry is where quality is kept or lost; a cure can't fix a bad dry.
Don't confuse with
- Curing: the finishing phase in sealed containers.
- Grow room: different climate targets and lights on.
- Freeze dryer: a machine, not a room (Contested method).
Terpenes are volatile hydrocarbon compounds built from five-carbon isoprene units; in cannabis they are made in the trichome heads and are a major part of aroma and flavour.Relative humidity is the water vapour in air as a percentage of what it could hold at that temperature, so the same RH dries plants differently at different temperatures.A dehumidifier removes water vapour from grow-room air, usually by condensing it on a cold coil; it is the main tool for controlling humidity in flower.A humidifier adds water vapour to the air to raise relative humidity, used mostly for clones, seedlings and veg, or dry climates.A carbon filter scrubs odour from exhaust air by passing it through activated carbon, which adsorbs aroma compounds such as terpenes.A grassy, hay-like aroma in dried cannabis caused by drying too fast, over-drying or bacterial activity; in GenetixBay's view it never fully cures out.The loss of volatile aroma compounds from cannabis through evaporation, oxidation and handling, fastest for monoterpenes and worst in warm, fast drying and poor storage.Drying fresh cannabis by freezing it and then removing ice under vacuum (sublimation) in hours or days; GenetixBay labels it Contested and does not recommend it.Drying harvested cannabis by hanging branches upside down in a dark, controlled room so buds dry slowly with even airflow around them.A drying rule of thumb: dry cannabis at about 60 °F (15.5 °C) and 60% relative humidity so buds dry slowly over roughly 10-14 days.A 0-1 measure of how freely available the water in a material is; for dried cannabis flower the accepted range is about 0.55-0.65 aw.A drying fault where a bud's surface dries too fast and seals, leaving the core wet; buds feel dry, then rehydrate and risk mould in the jar.
