How to dry cannabis: slow, cool and dark

Drying is where homegrown flower most often gets spoiled. Drying conditions affect aroma and handling quality, but “slow” isn’t automatically safer or better: flower that stays wet too long encourages microbial growth.

A common routine

1. Hang whole plants or branches upside down in a dark space.
2. Aim for around 60°F and 60 percent relative humidity. This “60/60” target is grower convention.
3. Keep air moving in the room, but don’t blow it directly on the buds.
4. One to two weeks is a common planning window, not a safety deadline. Bud size, airflow, how much you hang and room conditions all change the time needed. Check progress daily.

When is it dry?

• Bend a small stem. A snap is a rough handling cue. It isn’t a reliable measure of the moisture inside every flower or proof of microbial safety.
• The buds should feel dry outside but not crumble.
• A jar hygrometer can help you track moisture as it evens out, but let the reading stabilize at a steady temperature first; half a day isn’t a universal equilibration time. Cheap sensors can be inaccurate. A calibrated water-activity meter is the more appropriate way to check finished-flower aw.

Why moisture level matters

ASTM International’s specification for dry cannabis flower uses a water activity range of 0.55 to 0.65. The standard’s public summary uses this range to limit unwanted microbial growth and physical breakage. It isn’t proof that a batch is free of existing mold or toxins, and it doesn’t prescribe a drying time or room setting.

Common problems

• Changing smell: a grassy note can happen during drying, but a musty or ammonia-like odor, visible fuzz or decay needs inspecting right away. Don’t assume curing will fix it.
• Dried in a few days: too hot or dry. Next time, review temperature, airflow, flower size and room humidity together. Don’t add moisture blindly or create condensation.
• Too dry: a humidity pack at 58 or 62 percent can slowly restore some moisture. Don’t add fruit peel, bread or lettuce; they invite mold.

Keep suspicious or moldy flower out of the usable harvest. Don’t try to make it safe by cutting off visible mold, washing, drying, curing or extracting it. A humidity pack changes moisture. It doesn’t fix contamination or bring back lost terpenes.