Optimal Cannabis Storage Conditions: Temperature and Humidity Guide
Discover the perfect storage conditions for cannabis to maintain its potency and quality, focusing on temperature and humidity control.
Answer first: 62 percent is the storage target
Store cured cannabis flower at 62% relative humidity (RH). At that level, flower keeps enough moisture to stay springy and aromatic without giving mold a foothold. Drop much below 55% RH and trichomes dry out, terpenes fade, and flower crumbles. Push above 65% RH and sealed jars become a mold risk.
Why 62 percent instead of 58 or 65
Low humidity is a slow quality leak. Flower stored at 50% RH loses aroma and smoke quality within weeks. High humidity is a faster problem: trapped moisture creates pockets where mold spores germinate. The 58% to 62% range is the common buffer for cured flower, and 62% gives the most room before the mold threshold. Use 58% only for long-term storage in very dry climates.
cannabis storage conditions temperature humidity
What you need
- A digital hygrometer that reads in 1% increments
- Glass jars with airtight lids, sized to the amount of flower
- Two-way humidity packs rated at 62%
- A dark storage spot that stays between 60°F and 70°F
How to set and hold 62 percent humidity
- Calibrate the hygrometer with a salt test or a calibrated reference meter before trusting its readings.
- Confirm the flower is fully cured. Stems should snap, not bend, and the exterior should feel dry to the touch.
- Fill each jar about 75% full. Leave headspace so air can move and the pack can work.
- Place one 62% two-way humidity pack in each jar. Use a pack sized for the jar volume.
- Seal the lid and store the jar in a dark cabinet or closet at room temperature.
- Check the hygrometer daily for the first week. Open the jar for 10 minutes if RH reads above 65%.
- Move to weekly checks once the reading holds steady at 62% for three days.
- Replace the humidity pack when it turns stiff or the jar drifts below 58% RH for more than two days.
Signs the humidity is off
- Flower crumbles when squeezed: RH is too low, likely under 55%.
- Flower feels damp or clumps together: RH is too high, likely over 65%.
- A hay or ammonia smell appears: seal is trapping moisture and the cure is compromised.
- The hygrometer reads the same for weeks with no pack changes: verify the meter is working.
Common mistakes
- Storing in plastic bags. Plastic breathes unevenly and does not hold a stable RH.
- Packing jars tight. Compressed flower traps moisture and blocks air exchange.
- Adding fresh citrus or bread. These raise humidity fast and invite mold.
- Trusting a cheap analog hygrometer. Analog dials drift and can be off by 10% or more.