Quick answer

Dry cannabis at 60 to 70°F and 45-55% relative humidity. Use indirect airflow. Point fans at walls. Exchange room air 2-4 times per hour. Keep the room dark. Expect 7-14 days.

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Why humidity matters

Relative humidity controls drying speed. High RH (above 65%) slows drying and raises mold risk. Low RH (below 40%) dries buds fast. Fast drying locks in chlorophyll. It also loses terpenes. Target 45-55% RH for the first 5-7 days. Then raise to 55-62% for curing.

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Airflow basics

Airflow moves moisture away from buds. Stagnant air creates wet pockets. Mold grows in wet pockets. Use a small oscillating fan. Aim it at a wall or ceiling. Do not aim at buds. Direct airflow dries the outside of buds. The inside stays wet. That causes mold later.

drying cannabis 60% humidity 60 degrees

Fan placement and speed

  • Place one fan on the floor. Point it up at a 45-degree angle toward a wall.
  • Set fan to low speed. High speed disturbs trichomes.
  • Use an exhaust fan. Run it 24/7. It removes humid air. It pulls in fresh air.
  • Add a small clip fan for tents. Point it at the tent wall, not the plants.

Air exchange rate

Exchange room air 2-4 times per hour. A 4x4x6 foot room holds 96 cubic feet. A 50 CFM exhaust fan exchanges that air in about 2 minutes. Run exhaust on a timer. 15 minutes on, 15 minutes off works for most rooms. For small tents, run exhaust all the time at low speed.

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Monitoring tools

  • Hygrometer: measures relative humidity. Place it at bud level. Not on the floor.
  • Thermometer: keep 60 to 70°F. Above 75°F degrades terpenes.
  • Anemometer: measures fan speed. Optional. Aim for 0.5-1.5 mph at bud level.

Common mistakes

  1. Direct fan on buds. Causes case hardening. Outside dry, inside wet.
  2. No exhaust. Humidity climbs above 65%. Mold risk rises.
  3. High heat. Over 80°F evaporates terpenes.
  4. No dark period. Light degrades THC and terpenes.

Check buds daily. Bend a stem. It should snap, not crack. If it bends, dry longer. If it snaps, start curing. Burp jars for 10 minutes per day for the first week. Keep curing at 58-62% RH.